Preheat the oven to 425°F and prepare a cupcake pan by lining it with paper liners.

To create the streusel crumb topping, mix together the flour, brown sugar, and salt until combined. Add the melted butter, whisking until coarse crumbs form.

In a large mixing bowl, whisk together the flour, baking powder, and salt.

In another bowl, whisk the egg and granulated sugar until light and pale. Stir in the Greek yogurt, vegetable oil, and vanilla until smooth.

Gently fold the wet ingredients into the dry ingredients, being careful not to overmix.

Fold in the diced fresh strawberries, reserving a few for topping.

Mix the softened cream cheese, granulated sugar, cornstarch, and vanilla until smooth.

Spoon about one tablespoon of muffin batter into each cupcake liner. Add a scoop of cream cheese filling, and cover with more muffin batter until each cup is about two-thirds full.

Top with the prepared streusel and reserved strawberry pieces, pressing gently.

Bake at 350°F for 22-25 minutes until golden brown. A toothpick inserted should come out clean.

Cool in the pan for 5-10 minutes before transferring to a wire rack.

Stir the powdered sugar with milk or cream until the desired consistency is reached. Drizzle over cooled muffins.