PREHEAT oven to 350° F.
BEAT butter on medium to high speed for 30 seconds in large mixer bowl. Add brown sugar and eggs; beat until combined. Add frosting, peanut butter, baking soda, salt and cinnamon; beat until combined. Beat in as much of the flour as you can. Stir in oats and any remaining flour. Stir in morsels and raisins. Drop dough by rounded teaspoon 2 inches apart onto ungreased baking sheets.
BAKE for 12 to 15 minutes or until edges are light golden brown. Cool on baking sheets for 1 minute; remove to wire racks to cool completely.