In a mason jar or container, combine the milk, oats, 1/4 cup yogurt, protein powder, chia seeds, vanilla extract, cinnamon, and nutmeg. Stir well to ensure the protein powder is fully dissolved and no lumps remain—I always use a whisk for this to break up any clumps before refrigeration. Cover and refrigerate for at least 6 hours or overnight, allowing the oats to absorb the liquid and soften while the flavors meld together.

When ready to serve, whisk together the thick Greek yogurt and maple syrup until smooth and pourable. I like to use Greek yogurt for this topping because it adds a tanginess that complements the warm cinnamon flavors beautifully without making the drizzle too runny.

Remove the chilled overnight oat mixture from the refrigerator and give it a good stir, adding a splash of additional milk if the consistency is too thick. Pour the yogurt-maple syrup drizzle from Step 2 over the top and swirl it through or serve it on the side. Enjoy immediately, or keep refrigerated for up to 2 days.