This is my grandma's recipe for cornstarch frosting.
1c white sugar
1 Tablespoon Cornstarch
1 Tablespoon all-purpose flour
1 (.25 ounce) pakeage unflavored gelatin
1 teaspoon vanilla extract
1 Tablespoon butter
1 c heavy whipping cream
In a medium saucepan, mix together sugar, flour, cornstarch and gelatin. Add in eggs, mix until smooth and beat in milk. Cooking over medium heat, stirring occasionally until thick (3 to 5 minutes.). Remove from heat: add butter and vanilla. Let sit until completely cold. Once cold, beat until it forms soft, fluffy peaks. Whip Heavy cream into soft peaks and then fold into frosting.
Can frost one, 8in or 9in layer cake.