Bisquick is a pre-mixed baking mix sold by General Mills under its Betty Crocker brand, consisting of flour, shortening, salt, and baking powder (a leavening agent).ubstitution [edit]. One cup of Bisquick can be substituted by a mixture of one cup of flour, 1½ teaspoons of baking powder, ½ teaspoon of salt, and 2 1/2 tablespoons of oil or melted butter (or by cutting in 2 1/2 tbsp Crisco or lard).