Combine all ingredients except optional sweetener and berries in a small bowl and stir gently.
Taste and adjust sweetness if desired.
Divide mixture into small storage containers.
Top with berries. Store in the fridge at least 4 hours or overnight. (The mixture will thicken as it sits overnight in the fridge.) Serve cold.
Notes
This recipe will keep for 3-5 days when stored in airtight containers in the fridge.
Use ground raw oats or quick oats for a smoother final texture that the kids might prefer.
Try blueberries, raspberries, strawberries, diced mango, or mashed banana as the fruit.
Try chia seeds, hemp seeds, or ground flaxseeds to add fiber, protein and healthy fats. (Chia seeds may thicken the mixture more than hemp seeds.)
If you find the texture too thick, you can always stir in an extra tablespoon or two of milk.
You can blend the fruit right into the yogurt mixture for a smoother overall texture. This works well with strawberries and mango. Just put everything into a food process or blender and process until smooth.