Homemade Strawberry Rhubarb Cobbler with Buttery Crumble Topping - Quickie Treats

Ingredients

• 4 cups chopped rhubarb
• 2 cups chopped strawberries (1 quart)
• 3/4 cup granulated sugar
• 3 tablespoons cornstarch or quick-cooking tapioca
• 2 cups all-purpose flour
• 1 cup granulated sugar
• 2 teaspoons baking powder
• 1/4 teaspoon salt
• 3/4 cup cold salted butter, cubed (12 tablespoons)
• 1 teaspoon vanilla extract
• 1/2 cup boiling water