01 - In a medium bowl, combine rolled oats, almond milk, Greek yogurt, protein powder, cocoa powder, hazelnut butter, maple syrup, vanilla extract, and salt. Mix thoroughly until all ingredients are fully incorporated and the mixture is smooth and uniform.
02 - Divide the oat mixture evenly between two jars or airtight containers, ensuring both portions contain equal amounts for consistent serving sizes.
03 - Cover the containers and refrigerate overnight or for at least 4 hours. This resting period allows the oats to absorb the liquid completely and the flavors to meld together.
04 - Before serving, give the oats a thorough stir to redistribute any settled ingredients. Top each portion with chopped roasted hazelnuts, dark chocolate pieces, and an optional drizzle of hazelnut butter. Garnish with half a Ferrero Rocher chocolate if desired. Serve chilled.