BEAT cream cheese and Cheddar cheese in small bowl with electric mixer on medium speed until well blended. Add 1 Tbsp. of the bell peppers, the onions, Worcestershire sauce, lemon juice and ground red pepper; mix well. Cover.
REFRIGERATE several hours or overnight.
SPOON 2-1/2 cups of the cheese mixture onto large serving platter; shape into triangular shape to resemble a Christmas tree. Spoon remaining cheese mixture at the base of the triangle for the trunk. Decorate with the pesto and the remaining 1 Tbsp. bell peppers. Serve as a spread with RITZ Crackers.