Preheat oven to 375°F. Grease an 8-inch square baking dish
In a medium bowl, whisk together the flour, brown sugar, baking powder, and salt. Cut in the cold butter with a pastry cutter or two knives until the mixture resembles coarse crumbs.
Press the crumb mixture into the bottom of the prepared baking dish. Bake for 15 minutes or until lightly browned.
Meanwhile, in a medium bowl, combine the rhubarb, strawberries, granulated sugar, and cinnamon. Mix together until the fruit is evenly coated.
Spread the fruit mixture over the crust. Drizzle the melted butter over the top.
Bake for 15 minutes or until the fruit is tender and bubbly. Let cool for 10 minutes.
In a small bowl, whisk together the heavy cream and 2 tablespoons of granulated sugar. Drizzle the cream mixture over the cooled bars.
Let cool completely before cutting into bars.
Interesting Facts
Strawberry-rhubarb is a classic flavor combination.
Rhubarb is a vegetable, but it is treated as a fruit in cooking.