Pro tip: When using peanut butter, warm the peanut butter with 10 second increments in the microwave (stir in between), until it’s super soft (not hot) and drizzable. This will help you swirl it into the yogurt seamlessly for a beautiful marbled effect. It also makes the yogurt cups look more visually appealing. Plus, it helps the peanut butter flavor distribute more evenly in every bite.