For the cake: Combine the milk, chia seeds, vanilla, egg yolk and banana in a small microwave-proof jar or container (I prefer half-pint Mason jars). Add the flour and baking powder and stir until well incorporated and the batter thickens. Store in the fridge until ready to serve.
Microwave the jar on high for 1 to 1 1/2 minutes, then serve.
For the peanut butter cake: To the cake recipe, add the peanut butter and 1/2 teaspoon cinnamon and give everything a good stir. Once the cake is microwaved, drizzle some honey and sprinkle more cinnamon, if desired.
For the chocolate chip cake: To the basic recipe, add the chocolate chips and 1 tablespoon chopped walnuts. Once the cake is microwaved, top with the orange zest, more walnuts and honey, if using.
For the fig oatmeal cake: Omit the flour in the cake recipe, and substitute with the oats. Add the figs and cinnamon. Once the cake is microwaved, add the almonds, coconut flakes and a drizzle of maple syrup, if using.
It's crucial that you use a very ripe banana for the cake, because it's the only sweetener used. Although you can add in extra honey, maple syrup, Stevia or other sweetener of choice to the batter, I recommend adjusting as necessary after the cake has been microwaved.
Recipe courtesy of Min Kwon, M.S., R.D.