Banana Cupcakes with Blueberry Filling

Steps

1. Make the filling first so it can cool: in a small saucepan, stir the blueberries, one fifth of the granulated sugar, the lemon juice, the water and the cornstarch. Simmer over medium heat, stirring, 5–7 minutes until thick and jammy. Cool completely.
2. Preheat the oven to 350°F (175°C) and line a 12-cup muffin pan with paper liners.
3. Melt two thirds of the butter and let it cool slightly; keep the remaining one third soft for the frosting.
4. In a bowl, whisk the flour, baking soda, baking powder, salt and cinnamon.
5. In a large bowl, whisk the mashed banana, the melted butter, the remaining four fifths of the granulated sugar, the brown sugar, the egg, the Greek yogurt and two thirds of the vanilla until smooth.
6. Fold the flour mixture into the banana mixture just until no dry streaks remain.
7. Divide the batter among the liners, about two thirds full. Bake 18–22 minutes, until a toothpick in the center comes out clean.
8. Cool the cupcakes 10 minutes in the pan, then on a rack until completely cool, about 45 minutes.
9. Cut a small cone from the top center of each cupcake, spoon in the blueberry filling, and press the trimmed tops back on.
10. For the frosting, beat the cream cheese with the remaining soft butter until smooth, then beat in the powdered sugar and the remaining one third of the vanilla until fluffy.
11. Pipe or spread the frosting over the cupcakes. Chill leftovers.