Strawberry-Rhubarb Syrup

Combine strawberries and rhubarb in a blender; blend on low speed until smooth, 20 to 30 seconds. Strain through a mesh sieve placed over a bowl; discard solids and reserve juice.

Combine 1 cup water and sugar in a saucepan over medium-high heat; bring to a boil, whisking constantly. Stir in reserved strawberry-rhubarb juice.

Whisk cornstarch and 2 tablespoons water together in a small bowl until smooth; add to juice mixture and cook, whisking constantly, until thickened, about 1 minute.

Serve warm or cold.