Rhubarb and Semolina Gratin with Strawberry Sauce
Rinse and trim the rhubarb and cut into pieces. Pour 1/8 liter (approximately 1/2 cup) of water and sugar into a saucepan and bring to a boil while stirring. Add the rhubarb and blanch for 1-2 minutes. Remove the rhubarb with a slotted spoon, drain and place in a gratin dish (22 cm diameter) (approximately 9 inches).
Over high heat, boil down the rhubarb cooking liquid for 3-4 minutes. Pour in the milk and bring to a boil. Sprinkle in the semolina and simmer while stirring for 2-3 minutes. Remove from the heat and stir in the mascarpone. Separate the egg. Beat egg white until stiff. Stir the egg yolk into the semolina mixture. Fold the lemon zest into the egg whites. Pour over the rhubarb and bake in a preheated oven at 200°C (approximately 400°F) (gas mark 3, convection 180°C or approximately 350°F) for about 10 minutes.
Rinse and trim the strawberries and cut into small pieces, then puree together with the vanilla. Serve the rhubarb gratin topped with the strawberry sauce and garnished with lemon balm.