HEAT oven to 400ºF.
CORN Muffins: Prepare muffin batter as directed on package; stir in chiles, cumin and oregano. Spoon into 12 paper-lined muffin cups, filling each cup half full. Bake 20 to 25 min. or until toothpick inserted in centers comes out clean. Cool 10 min. Remove muffins from paper liners; crumble into large pieces.
SALAD Dressing: Mix sour cream and dressing.
SALAD: SPREAD half the crumbled Corn Muffins onto large platter. Cover with layers of all remaining Salad ingredients except bacon; top with remaining crumbled muffins, bacon and Salad Dressing. Serve immediately.