Magic Apple Plum Cobbler

1/2 cup (115 grams or 4 ounces) unsalted butter
1 cup (130 grams) all-purpose flour
1 cup (200 grams) sugar, divided
1 1/2 teaspoons baking powder
1/2 teaspoon fine sea or table salt
3/4 cup (175 ml) whole milk
2 medium apples, peeled
3 small or 2 medium plums, no need to peel (and/or peaches)
3/4 teaspoon ground cinnamon
 
Heat the oven to 350°F.  Place butter in a 2 to 3-quart baking dish or a 7×11-inch cake pan.  Place pan in oven for 5 to 7 minutes, until butter has melted.  Tilt the dish to ensure it is evenly coated with butter.
 
Whisk together the flour, 3/4 cup sugar, baking powder, and salt in a small bowl and stir in milk. Mix until smooth.  Pour batter over the butter but do not stir, even if it looks like a puddle-y buttery mess.
 
Cut apples into 8 wedges, small plums into 4 wedges and medium ones into 4 to 6.  Space fruit over batter.  Sprinkle with cinnamon and then remaining sugar
 
Bake the cobbler until it is set and golden on top, 35 to 40 minutes. Cool slightly on a rack. Serve the cobbler warm or at room temperature.

Serves 8 to 10.

From Smitten Kitchen