This absolutely wicked 'Tim Tam' Tart was extremely indulgent & so very moreish. The gluten free recipe following is my conversion of the Cook the Cover recipe from Taste magazine's April 2017 edition. Most Australians will know what a Tim Tam is but for those who don't Tim Tam is a much loved chocolate biscuit made by Arnott's.
Most of the tart can quite easily be made gluten free by choosing the appropriate chocolate. The parts of the tart that need to be made gluten free are the 'Tim Tams' for decoration & tart base. You could use manufactured chocolate biscuits however if they contain rice flour the biscuits may be a little gritty & this will impact on the texture of the tart.
The following recipe for the 'Tim Tam' Biscuit base is my guesstimate based on the specified ingredients for Arnott's dark chocolate Tim Tams, including the percentage of chocolate. Basically I weigh the icing, chocolate & biscuit separately then I estimate the individual percentages & try to work out the ingredient amounts for each of those. One thing that I know is a little 'out' is the amount of golden syrup in the biscuit. The biscuits are pretty similar however there are some ingredients that I haven't added for example colours & flavours. The following photo shows my biscuits compared with a dark chocolate coated Tim Tam base.
Another thing that I can't quite get right is the icing between the biscuits. It is a little hard to make the icing exactly like the real thing as commercial manufacturers usually make it with sugar, vegetable oil & emulsifiers. Emulsifiers are not something that I have on hand in my kitchen so I've used chocolate & butter in the recipe below as they both contain emulsifiers (butter naturally contains an emulsifier). I have other icing recipes on the website that would work very well & have put in the links after the list of icing ingredients.
The following biscuit base recipe is sufficient to make approximately 10 whole biscuits & 120 g of unfinished biscuit for the base of the tart.
This recipe was designed specifically to be made with Bakers' Magic gluten free flour. The finished baked product will not be the same if you use another gluten free flour and you will need to adjust the recipe, particularly if the flour you're using contains rice flour.
'Tim Tam' Biscuit base
Dry ingredients
150 g Bakers' Magic Gluten free flour
1/2 tsp Baking powder
40 g Caster sugar
15 g Cocoa
Wet ingredients
0 - 20 g Golden syrup
75 g Butter
2 tsp Vanilla
Golden syrup - Is specified in the ingredients on the packet but you don't need to add it if you don't want to. Increasing the amount of golden syrup will increase the hardness of the biscuit. I used 20 g next time I make them I will use 10 g.
Chocolate Icing for the biscuits*
50 g Dark chocolate
20 - 50 g Butter
70 g Icing sugar
Chocolate Icing - There is minimal water in the icing as we want the sandwiched biscuits to remain crunchy. Provided the icing used to sandwich the biscuits contains minimal water/liquid you can use any icing. For example Magic Chocolate Topping with some additional peppermint oil, Whipped Peanut Butter icing or Chocolate creme icing.
You will need extra dark chocolate for coating the iced biscuits.
Tart Base
120 g 'Tim Tam' biscuit base
120 g Dark Chocolate (melted)
60 g Chocolate icing for the biscuits
35 g Butter (melted)
Milk Chocolate Ganache
400 g Milk chocolate
250 g Thickened cream
50 g Butter
1 tsp Vanilla
1/2 tsp Salt flakes
Dark Chocolate Ganache - Taste recipe
150 g Dark chocolate 70%
50 g Butter
Chocolate Ganache - my alternative
90 g Thickened cream
150 g Good quality dark chocolate
Dark Chocolate - the original recipe used 70% dark chocolate with a minimal amount of butter. I stored the tart in the fridge & found that the top chocolate layer would crack when cutting. In addition my daughter & husband felt that the 70% chocolate was a tad too bitter. When I make the tart again I will use my alternative chocolate ganache (maybe with a mix of 70% & 54% chocolate).
Dark Cocoa powder to serve
+
300 ml Double cream whipped to soft peaks
Method
Biscuit Base
Mix together the dry ingredients, Bakers' Magic flour, baking powder, cocoa & sugar.
Melt the butter & add in the other wet ingredients.
Combine the wet & dry ingredients. Bring the dough together with your hands, put it into a container and chill in the fridge for ~15 mins.
Turn oven on to 1500 - 1600 C - fan forced. If you have a hot oven use 1500.
Knead the dough until it is pliable. Roll out to a height of ~2 mm between two sheets of baking paper. I made some that were 3 mm but they were too high as a finished biscuit so I settled on the the 2 mm & they were great. I used my 2 mm spacer on either side of the dough when I was rolling it out to get all the dough to the same height.
You will need 120 g of cooked biscuit for the tart base and at least 20 rectangles for the finished 'Tim Tams' for decoration. You may need a few more in case some break etc. Basically cut out as many 3 cm x 6 cm rectangles as you want to & bake the rest of the dough as scraps.
Transfer dough rectangles and scraps to a lined baking tray and prick the tops ~5 times with a fork.
Bake for a total of ~10 mins. Turn the tray halfway through baking. Gently push down on any biscuits that are lifting off the tray.
Bring tray out of the oven & allow the biscuits to cool before icing them.
Icing
Melt the butter & chocolate together. You will use some of the icing to sandwich the biscuits together & some to go in to make the base of the tart.
Mix in the sifted icing sugar. The icing will be thick & not free flowing. Transfer the icing to a piping bag fitted with a flat nozzle (easiest nozzle to use) or a size 9 round nozzle.
Pick the best 20 biscuits, that is ones that are relatively flat & are the same size. Lay 10 of them on the baking tray with the fork indentations facing down.
Pipe a stripe of the icing on the biscuit & place another biscuit base on top (with the fork indentations facing up). Gently press down on the top biscuit to sandwich them together.
Making the base
Grease a 11 cm x 35 cm fluted tart tin with removable base.
Melt the butter & chocolate together. Add in the icing & mix to combine. Set aside to cool for ~5 mins.
Use a food processor to blitz the biscuits/baked scraps until they are fine crumbs.
Add in the chocolate mix & process until combined.
Press the chocolate/biscuit mix over the base & sides of the prepared tin. If the mixture is too tacky let it cool for ~5 mins before pressing into the tin.
Place in the freezer for 15 mins.
Milk Chocolate Ganache
Essentially you combine all the ingredients & warm the mixture until everything is melted & the mixture is smooth.
Microwave
Add ingredients to a microwave-safe bowl & microwave on high for ~30 secs. Stir the mixture & repeat until the chocolate has melted.
Thermomix
Add all ingredients to the TM bowl & mix @ 500 C speed 4 for 4 mins. Check that all the chocolate is melted, if it hasn't heat/mix for a little longer.
Stove top
Add the cream, butter, salt & vanilla to a medium sized saucepan. Heat the mixture over medium heat until the butter has completely melted & the cream is getting hot (but not boiling). Take the saucepan off the heat & add in the chocolate. Let it sit for ~2 mins before stirring the mixture. The chocolate should melt with the heat of the cream.
All methods
Depending on how hot the milk chocolate ganache is you may need to let it sit for a little while ~5 mins before pouring over the tart base.
Place in the fridge for 2 hours, until just set.
Coating the 'Tim Tams'
Melt some compound dark chocolate in a small container (microwave safe bowl or bowl above simmering water).
Put a piece of paper on your kitchen bench & place a cooling rack above it.
Put an uncoated biscuit into the melted chocolate & use 2 forks to completely coat the chocolate. There are 2 options for getting the biscuit out of the chocolate & putting it on the cooling rack, using utensils (like the forks) or using your fingers. Using your fingers is easier but messier.
Working quickly repeat for the remaining biscuits.
Bang the cooling rack on the bench to knock off excess chocolate. Optional - make stripes on the top of the chocolate with a fork. Get a hair dryer (yes you are reading correctly) & blow hot air over the top of the chocolate. The stripes should be less obvious & the chocolate should have a wavy pattern.
Carefully transfer the biscuits to a lined baking tray.
Dark Chocolate ganache
Regardless of which chocolate ganache you'll make the chocolate needs to be melted. The chocolate can be melted in the microwave, Thermomix or on stove top - use the methods for the milk chocolate ganache. Be careful with over heating the chocolate if you are using 70% (or dark couverture chocolate), try to keep the melted chocolate below 450 C.
Remove tart from the fridge. Quickly pour the dark chocolate ganache over the milk chocolate ganache, spread to the edges. Gently tap & shake the tart on the bench to get rid of air bubbles in the ganache & to make the surface of the ganache smoother.
Put the tart back in the fridge for ~15 - 20 mins until the ganache is set.
Assembling
Bring the tart out of the fridge ~20 mins before serving it. Transfer to a serving plate.
Use a balloon whisk to whip the double cream. It is so quick & you have more control over the whipping process.
Cut the chocolate coated 'Tim Tams' in half diagonally.
Put dollops of the whipped cream along the tart & top with the cut 'Tim Tams'.
Dust with a little cocoa.
Simply enjoy!