Lemon Sour Cream Frosting
["2 Tbsp. soft butter", "2 1/2 c. confectioners sugar", "1/4 c. sour cream", "1/8 tsp. salt", "2 tsp. grated lemon peel"]
["Cream butter and sugar; add salt, sour cream, lemon juice and peel.", "Beat until light and fluffy."]
["butter", "confectioners sugar", "sour cream", "salt"]