Toast the pecans: Add chopped pecans to a dry skillet over medium heat. Stir for 3–5 minutes until fragrant and lightly browned.
Set aside to cool.
Mix the base: In a medium bowl or large jar, whisk milk, Greek yogurt (or protein powder), maple syrup, vanilla, cinnamon, and a tiny pinch of salt until smooth.
Stir in chia seeds: Sprinkle chia seeds over the liquid and whisk well to distribute. Let it sit for 5 minutes, then whisk again to prevent clumps.
Rest and thicken: Cover and refrigerate for at least 2 hours, ideally overnight. The mixture will thicken to a pudding-like texture.
Adjust consistency: If it’s too thick, stir in 1–3 tablespoons more milk.
If it’s too thin, add 1–2 teaspoons more chia seeds and chill 15–20 minutes.
Fold in pecans: Stir in most of the toasted pecans, saving a little for topping.
Serve: Spoon into bowls or jars. Top with remaining pecans and a small drizzle of maple syrup. Add berries or a dollop of yogurt if you like.