Another recipe that calls for sour milk.
From a box sold in San Antonio, Texas.
Drop Brownies
1/2 c. Crisco
1 c. brown sugar
1 egg
1/2 c. sour milk
2 sq. chocolate (melted)
1 1/2 c. flour
1/4 t. baking powder
1/4 t. baking soda
1 cap vanilla
1 c. chopped nuts
Drop + bake 400 deg. to 425 deg. for 10 to 12 minutes. Ice while warm.