Preheat oven to 375°F (190°C). Line a 12-cup muffin tin with paper liners or lightly grease.
In a small bowl, mix cream cheese, sugar, egg yolk, and vanilla extract until smooth. Set aside.
In a large bowl, whisk flour, sugar, baking powder, baking soda, and salt.
In another bowl, whisk eggs, milk, oil, and vanilla until combined.
Add wet ingredients to dry ingredients and stir gently until just combined.
Toss diced strawberries with 1 tablespoon flour, then gently fold into the batter.
In a small bowl, mix flour and sugar for the crumb topping, then stir in melted butter until crumbly.
Fill muffin cups halfway with batter. Add about 1 teaspoon of cream cheese filling to the center of each. Cover with remaining batter.
Sprinkle crumb topping evenly over each muffin.
Bake Strawberry Cream Cheese Muffins for 18–22 minutes until golden and set.
Cool 5 minutes in the pan, then transfer to a wire rack to cool completely.