Heat oven to 350ºF. Heat dressing in large deep skillet on medium-high heat. Add onions, carrots and garlic; cook 3 to 5 min. or until carrots are crisp-tender, stirring occasionally. Stir in curry powder, lentils and remaining broth; cook 3 to 5 min. or until thickened. Stir in peas. Spoon into 8-inch square baking dish; cover with potato mixture.