Preheat your oven to 350°F (175°C). Grease and flour the baking pan.
In a mixing bowl, combine the yellow cake mix, strawberry jam, strawberry jello mix, vegetable oil, melted butter, eggs, and buttermilk. Mix until smooth.
Pour the batter into the prepared baking pan and bake for 30 minutes or until a toothpick inserted in the center comes out clean.
While the cake is baking, prepare the glaze by mixing powdered sugar, strawberry jam, milk, and vanilla extract in a small bowl until smooth.
Once the cake is done, let it cool for a few minutes before drizzling the glaze over the top.
Notes
You can add fresh strawberries on top for decoration if desired.