1. Beat first 3 ingredients at medium speed with an electric mixer until creamy.
2. Gradually add powdered sugar alternately with 1 Tbsp. milk and orange juice, beating at low speed until blended and smooth after each addition.
3. If desired, beat in remaining 1 Tbsp. milk, 1 tsp. at a time, until desired consistency. Beat in food coloring until blended, if desired.