Start by chopping mushrooms and onions in small cubes. Pour a little oil on a pan and fry the onions. Add the mushrooms and fry for a few minutes. Cut green asparagus into smaller pieces and fry on pan for 2-3 minutes. Turn off the pan and save for later.
Turn on the oven at 200c.
In a pan add plant butter. Once melted, Tapioka is added. Whisk together to a flour bowl with a whisk. Stir in the plant milk and keep stirring under medium heat. Put 1 vegetable broth in the pan with 100ml. water. Let it boil thickly while stirring constantly. Be patient it will take a few minutes.
Cut the white asparagus into mouth-watering pieces. Add them to the sauce along with peas, fried onions, mushrooms and asparagus. Add chopped parsley.
Put the tartlet shells on a grill and heat them in the oven for 2-3 minutes. Pour the filling into the warm, crispy tartlets. Garnish with parsley, sprinkle with salt and pepper.