Using pieces of cellophane (or cellophane bags), wrap each tree individually and tie with ribbon or twine to give out as gifts this Christmas.
Melt butter and marshmallows in a large saucepan over medium heat, stirring. Remove from heat and stir in Rice Krispies and 15 drops green food coloring.
Line a baking sheet with parchment; grease hands with oil. Form 12 small cone shapes, using about 1/2 cup mixture for each. Let cool on baking sheet, about 15 minutes.
Pipe frosting on 1 tree to create string for lights. Add mini M&M's for bulbs. Lay each gumdrop on its side; cut it crosswise into 3 slices. Use frosting to adhere 1 flat slice to top of tree and 1 Rolo to bottom for trunk. Repeat with remaining trees. Let frosting dry completely, 2 to 3 hours, before wrapping.
GIVE THEM Using pieces of cellophane (or cellophane bags), wrap each tree individually and tie with ribbon or twine.