In a medium bowl or meal prep container, combine rolled oats, vanilla protein powder, chia seeds, cinnamon, and nutmeg. Stir the dry ingredients together to evenly distribute the spices and protein powder.

Add Greek yogurt, milk, vanilla extract, and maple syrup. Stir thoroughly until the mixture becomes smooth and creamy. Ensure the protein powder is fully incorporated with no dry pockets remaining.

Fold in the freshly grated carrot, raisins, and half of the chopped nuts. Mix gently so the carrots are evenly distributed throughout the oat mixture.

Cover the container and refrigerate for at least 4 hours or overnight. When ready to serve, stir well and top with remaining nuts and additional grated carrot if desired.