Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking pan.

In a large bowl, beat the softened butter and granulated sugar until light and fluffy. Add the eggs and vanilla extract, mixing well.

In a separate bowl, combine flour, baking powder, and salt. Add dry ingredients to wet ingredients, alternating with milk, and mix until just combined.

Spread half of the batter into the prepared baking pan.

In a small bowl, mix together brown sugar and ground cinnamon. Add melted butter and stir until well combined.

Drop spoonfuls of the cinnamon-sugar mixture over the base batter.

Add the remaining batter on top. Use a knife to swirl the cinnamon mixture throughout the batter, creating a marbled effect.

Bake the Cinnamon Roll Bliss Bars for 25-30 minutes, or until a toothpick inserted into the center comes out clean.

Allow the bars to cool completely on a wire rack.

In a large bowl, beat the softened cream cheese and butter until smooth.

Add the powdered sugar and vanilla extract, mixing until well combined.

Gradually add milk, 1 tablespoon at a time, until the frosting reaches a spreadable consistency.

Spread the cream cheese frosting evenly over the cooled Cinnamon Roll Bliss Bars.

Cut the bars into squares and serve.