Pour the strawberry mixture into a bowl or container and add the oats and chia seeds. Stir well to combine. If your yogurt was on the thin side, let the overnight oats rest for 30 minutes before mixing again.
Refrigerate, covered, for at least four hours or overnight. Serve cold. Keep in the container or divide into jars and layer with toppings for individual servings. Keep up to three days.
Notes
Use about 100 ml (~⅓ cup) of milk if using frozen strawberries. The mixture will be thick but remember that the berries are going to thaw in the refrigerator.Storage: keep in the refrigerator, covered tightly, for up to three days. Because this is made with fresh fruit blended in, it doesn't last as long as plain overnight oats before the berries make it start to taste off.