1) Spread the bread with the butter, and sprinkle with cinnamon-sugar. Cut it into 1/2" cubes.
2) Layer the buttered bread with the berries in a microwave-safe bowl.
3) Whisk together the egg, milk, vanilla, and sugar. Pour over the bread and berries in the bowl, stirring gently to combine.
4) Microwave for 2 minutes, uncovered. Check and see if it's still liquid. If it is, microwave in 30-second bursts, till pudding is cooked all the way to the center; the very center can still look a bit uncooked, but it shouldn't be liquid.
5) Remove from the microwave. Garnish with fresh berries, if desired. Serve warm; whipped cream or ice cream are always welcome.
Yield: 1 large or 2 smaller servings.