Cook caramels and 2 Tbsp. ricotta in large nonstick skillet on medium-high heat 3 to 5 min. or until caramels are completely melted and mixture is well blended, stirring constantly. Add remaining ricotta and pumpkin; cook 20 to 25 min. or until mixture is thickened and starts to pull away from side of skillet, stirring constantly. Stir in cardamom.