If you can't get your hands on egg replacer, you can make an easy egg substitute with ground flaxseed! Just mix 1 tablespoon of ground flaxseed with 2 tablespoons of water for each egg called for in the recipe. So for this vegan gingerbread cake recipe, you'll need two tablespoons of ground flaxseed and 1/4 cup of water. Mix those together and let them sit for about 5 minutes to thicken. Then mix into the recipe as usual. When you're using a flax egg, you may want to add an extra 1/4 tsp of baking soda to your dry ingredients to make up for the baking soda you're missing from the egg replacer.