Make the filling

1. In a small bowl, combine the sugar and cornstarch.
2. In a medium saucepan, combine rhubarb, strawberries and lemon juice. Cook, stirring occasionally, until the fruit is soft (about 8 minutes). Stir in the sugar mixture and cook, stirring constantly, until the mixture comes to a boil and thickens (about 1 minute). Remove from heat.

Make the crust and topping

1. Preheat oven to 350° F or 325°F Convection.
2. Line a 9 x 13” pan with two sheets of parchment, one crosswise and one lengthwise, so that they form slings to remove the squares when cooked.
3. In the bowl of a stand mixture fitted with the paddle attachment, beat all the dry ingredients until they resemble coarse crumbs.
4. Reserve 225 g or 1 ½ c of the mixture for the top. Press the remaining mixture to form an even layer in the bottom of the prepared pan. Spread the filling over the crust. Sprinkle with the reserved crumb mixture.
5. Bake until golden brown (30 – 35 minutes). Cool completely.

Make the drizzle

1. Mix the powdered sugar and milk until smooth. Drizzle over cooled bars, and cut into 2” squares.