Step 1: Gather Your Ingredients. Make sure your Dr Pepper is thoroughly chilled. If using canned full-fat coconut milk, ensure it's been refrigerated for several hours (preferably overnight) so the cream has separated and solidified at the top.
Step 2: Prepare Your Glass. Fill a tall glass with plenty of ice. Good ice makes a difference; large cubes or spheres melt slower, keeping your Dirty Dr Pepper from getting watered down too quickly.
Step 3: Add the Coconut Cream. Carefully scoop 2 tablespoons of the thick, chilled coconut cream into the bottom of your glass. If your coconut cream is very firm, you might need to gently press it against the side of the glass with a spoon to help it mix later.
Step 4: Squeeze in the Lime Juice. Add 1 tablespoon of fresh lime juice to the glass. This is a starting point; you can always add more later if you prefer a tangier Dirty Dr Pepper.
Step 5: Pour in the Dr Pepper. Slowly pour the chilled Dr Pepper over the coconut cream and lime juice. As you pour, the carbonation will help begin to emulsify the cream, creating a beautiful swirling effect.
Step 6: Stir Gently. Use a spoon or a stirring stick to gently incorporate the coconut cream and lime juice into the Dr Pepper. Stir just enough until the cream is mostly dissolved and the drink has a cloudy, pale brown appearance. Don't over-stir, as you want to preserve some of the carbonation.
Step 7: Garnish and Serve. Garnish your Dirty Dr Pepper with a fresh lime wedge on the rim of the glass and, if desired, a maraschino cherry for an extra touch of sweetness and color. Serve immediately and enjoy!