Halve the tomatoes, wash the asparagus and cut into 3 - 4 cm long pieces. Cut the spring onions into thin rings.
Heat some oil in a pan and sauté the asparagus over medium heat, at the same time add the pasta water. The noodles should be cooked just before the sauce is finished.
After 5 - 7 minutes add the spring onions, tomatoes and lemon juice to the asparagus.
Mix the vegetable stock and first pour 150 ml of it into the pan - only add the rest if necessary. Then add the cream and season the sauce with salt and pepper. If necessary, add more vegetable stock and, if necessary, add a dash of milk.
Mix 3 teaspoons of flour and a little water into a flour dough and mix with the sauce. Then grate the parmesan and stir in. If necessary, add a little salt and pepper.
Arrange everything on the plate and serve with finely chopped wild garlic as a topping.