Chocolate-Strawberry Cupcakes

Name: Chocolate-Strawberry Cupcakes
Cook time: 1 h
Total time: 1 h
Cuisine: American
Ingredients: 1 cup all-purpose flour; 1/2 teaspoon salt; 1/2 teaspoon baking soda; 1/2 cup unsweetened cocoa powder; 1 teaspoon instant espresso powder; 3/4 cup whole milk; 1 cup granulated sugar; 3/4 cup vegetable oil; 1 large egg; 1 teaspoon pure vanilla extract; 1/4 cup strawberry preserves or jelly; 1 teaspoon fresh lemon juice; 6 ounces semisweet chocolate, finely chopped; 12 medium strawberries; 2 ounces white chocolate, finely chopped; 1 1/2 sticks (12 tablespoons) unsalted butter, at room temperature; 2 pinches salt; 2 cups confectioners¿ sugar; 2 teaspoons pure vanilla extract; 2 tablespoons whole milk