Make the vanilla base: In a medium bowl, whisk 1 1/2 cups milk, 1/2 cup Greek or coconut yogurt (optional), 1–2 tablespoons maple syrup or honey, 1–1 1/2 teaspoons vanilla extract, and a small pinch of salt.
Add chia seeds: Whisk in 1/2 cup chia seeds until evenly distributed, breaking up any clumps.
Let it thicken: Rest the mixture for 10 minutes, then whisk again to prevent settling.
Cover and refrigerate for at least 2 hours, or overnight, until thick and pudding-like.
Prep the berries: If using strawberries, hull and slice. If using frozen berries, thaw and drain excess liquid. Toss with a squeeze of lemon and a touch of sweetener if you like.
Assemble the cups: Spoon chia pudding into jars or small glasses, alternating with layers of berries.
Top with a few extra berries and any toppings you like.
Chill briefly (optional): For a cleaner set, chill the assembled cups for 15–30 minutes before serving.
Serve: Enjoy cold, and store the rest covered in the fridge.