Question: what can you substitute 1 egg with?
Answer: Vinegar & baking soda. Replace 1 egg with: 1 teaspoon baking soda, 1 tablespoon vinegar. ... 
Unsweetened applesauce. Replace 1 egg with: 1/4 cup applesauce. ... 
Plain or vanilla soy yogurt. Replace 1 egg with: 1/4 cup yogurt. ... 
Silken tofu. ... 
Ripe banana. ... 
Ground flaxseed.