Baking Tips & Tricks Cake How to calculate how much cake mixture you need for a number cake Back to Cake Cake How to calculate how much cake mixture you need for a number cake Number cakes look stunning, but it can be frustrating to buy a tin and not know what recipe to follow to bake your cake. This simple tip provides the solution we have all been looking for, no matter which number tin you have bought. Method If you have a go-to sponge cake recipe for an 8" tin, fill two 8" sandwich tins with water up to the level that you would with cake mixture (usually 2/3 full) Empty the water from the tins into a measuring jug. This will be the quantity of mixture require for one cake using your favourite recipe. Pour the water into the number tin. Repeat this process until the number tin is 2/3 full. Count the amount of times that you have to measure the water and this will calculate how many times the recipe you will need to use. For example; filling the number tin with 2 lots of water will mean you need to double your usual recipe. 3 lots of water - triple your recipe and so on.