Make the coffee mixture: Dissolve the dark roast instant coffee in hot water. Set aside to cool.
Prepare the oat base: Blend your oats in a mixer until smooth. In a mixing bowl, combine blended rolled oats, unsweetened cocoa powder, milk, maple syrup, chocolate protein powder, and vanilla extract. Add the cooled coffee mixture and mix well.
Assemble the creamy topping: In a separate bowl, combine Greek yogurt, sweetened condensed milk, vanilla extract, sour cream, and vanilla ice cream protein powder. Whisk until smooth.
Layer and refrigerate: In a jar or container, layer the oat mixture and creamy topping. Cover and refrigerate for at least 4 hours or overnight.
Serve: Top with a dusting of unsweetened cocoa powder just before serving.
Notes
(1) You can leave the oats unblended too! I just prefer the texture of blended oats more - I think it tastes like brownie batter.(2) Store in airtight jars in the fridge up to 3–5 days.(3) If mixture thickens too much, stir in a splash of milk before eating.(4) To warm, microwave for ~20–40 seconds (test jar safety).(5) Swap dairy ingredients for plant-based alternatives for vegan version.(6) Omit or swap protein powder as desired; adjust texture and sweetness accordingly.