How to Make French Buttercream Frosting
- Begin by setting out all ingredients several hours before beginning, so everything is at room temperature.
- Have ready a greased 1-cup heat-proof glass measuring cup near your stove.
- In a bowl, beat the yolks with an electric mixer until light in color.
- Meanwhile, combine the sugar and corn syrup in a small saucepan (do not use a non-stick sauce pan). Heat, stirring constantly, until the sugar dissolves and the syrup comes to a roiling boil. Immediately transfer the syrup to the prepared glass measuring cup to stop the cooking.
- If using a hand-held mixer, beat the syrup into the yolks in a thin, steady stream. Don't allow syrup to fall on the beaters or they will spin it onto the sides of the bowl. If using a stand mixer, pour a small amount of syrup over the yolks with the mixer turned off. IMMEDIATELY beat at high speed for 5 seconds. Continue with the remaining syrup. For the last addition, use a rubber scraper to remove the syrup clinging to the glass measuring cup. Continue beating until completely cool.
- Gradually beat in the butter and flavoring. Place in an airtight bowl.
- Will keep for 6 hours at room temperature, 1 week refridgerated, or 8 months frozen. Be sure to bring to room temperature completely before rebeating to restore texture, or the frosting may curdle.