Combine flax meal and water in a small bowl and let gel for 5-10 minutes.
Cream the butter and sugar together until light and fluffy.
Add flax eggs and vanilla, beat until incorporated
Add vegan sour cream and mix again until incorporated
In another bowl, sift together flour, baking soda and baking powder.
Mix dry ingredients into the wet mixture, and scoop 1-inch balls onto a greased cookie sheet and bake for 12 minutes. (It's a really sticky batter, but that's totally normal)