Plum snack cake with Pecan Topping

Ingredients

• 1 ¼ cups all-purpose flour
• 1 teaspoon baking powder
• ¼ teaspoon salt
• 1/3 cup whole milk
• 1 teaspoon vanilla extract
• ¾ cup sugar
• 6 tablespoons unsalted butter at room temperature
• 2 eggs, at room temperature
• 5 medium plums, pitted and cut into ¾ -inch pieces