This is a really simple, delicious crumble that you can adapt with any of your favorite frozen berries. From Meal in a Mug: 80 Fast, Easy Recipes for Hungry People—All You Need Is a Mug and a Microwave.
Prep/cook time: 3 minutes
½ cup mixed frozen berries (raspberries, blueberries, or blackberries)
1 teaspoon light brown sugar
1 teaspoon cornstarch
For the topping
¼ cup rolled oats
2 teaspoons light brown sugar
¼ teaspoon ground cinnamon
1 teaspoon butter, melted
1. Put the berries in a small mug; they should almost come up to the top. Sprinkle the brown sugar and cornstarch over them and microwave on high for 30 seconds. Stir gently so you don’t break up the berries, then microwave on high for 30 seconds, or until the sauce starts to thicken.
2. Make the topping. Put the oats in a small cup or bowl and stir in the brown sugar, cinnamon, and melted butter. Spoon the topping over the berries and stand the cup in a microwaveable shallow bowl, in case any of the sauce bubbles over. Microwave on high for 1 minute 20 seconds.
3. Allow to stand for 1 minute before serving with a scoop of vanilla ice cream or a splash of heavy cream.