Preheat oven to 350°F. Line a muffin tin with cupcake liners. This helps cupcakes bake evenly and prevents sticking. Prepare all ingredients before starting for a smooth baking process.

In a large bowl, mix flour, sugar, baking powder, and salt. Stir well so everything is evenly combined. This dry mix gives structure and softness to your cupcakes.

In another bowl, whisk milk, melted butter, eggs, and vanilla extract. Mix until smooth and fully combined. This creates a rich and moist base for your cinnamon roll cupcakes.

Slowly add wet mixture into dry ingredients. Stir gently until just combined. Do not overmix because it can make cupcakes dense instead of soft and fluffy.

In a small bowl, mix brown sugar, cinnamon, and melted butter. Stir until it becomes a thick cinnamon swirl mixture. This adds that classic cinnamon roll flavor.

Fill cupcake liners halfway with batter. Add a spoon of cinnamon swirl mixture on top. Use a toothpick to gently swirl it into the batter for a marbled effect.

Bake cupcakes for 18 to 22 minutes until golden and a toothpick comes out clean. Let them cool in the pan for a few minutes before transferring to a rack.

Beat cream cheese, butter, powdered sugar, vanilla, and milk until smooth. Spread frosting on cooled cupcakes. Enjoy soft, sweet cinnamon roll cupcakes fresh or store for later.