Preheat the oven to 350 degrees F. Line a 9x13 inch baking dish with parchment paper.In a large bowl, whisk together the flour, baking powder, cardamom, and brown sugar. Add the butter, milk, eggs, bourbon (if using), and vanilla, mix until just combined. Spoon the batter into the prepared pan. Sprinkle the cherries and strawberries over the batter, pressing the fruit gently into the batter.To make the crumble. Whisk together the flour, sugar, and cinnamon in a small bowl. Add the butter and mix with your hands until the mix is moist and a crumble forms. Sprinkle the crumble evenly over the fruit. Transfer to the oven and bake for 45-55 minutes or until golden on top. If you insert a skewer into the center, it should come out almost clean. Let the cake cool for 5 minutes. Serve warm or at room temp. If desired, dust with powdered sugar. Serve with vanilla ice cream.