For the crust: Combine the flour, salt and vegetable shortening in a food processor. Pulse until the mixture resembles rough breadcrumbs. Add the ice water, 1 tbsp at a time, and pulse between additions until a rough dough comes together.
Turn out the dough onto a floured surface and knead briefly. Wrap in plastic wrap and chill for 30 minutes.
After 30 minutes, remove the dough from the fridge and preheat the oven to 325°F.
Divide the dough in half. Roll out each piece on a lightly floured surface to approximately 0.75 cm | 0.333" thickness.
Use them to line the base and sides of fluted tartlet or mini quiche pans. Cut away any overhanging excess pastry and prick the bases with a fork. Chill until needed.
For the filling: Heat the olive oil in a small frying pan set over a medium heat. Add the shallot and a pinch of salt, sweating until softened, about 5-6 minutes. Set the pan to one side.
Beat together the sour cream, milk, eggs and Parmesan with plenty of salt and pepper in a mixing bowl.
Arrange the sweated shallot, smoked salmon and chopped asparagus between the lined pastry crusts before placing them on a baking sheet.
Carefully ladle over the beaten egg mixture, filling them just short of their rims. Sprinkle with chopped dill and season with freshly ground black pepper.
Bake for about 35-45 minutes until the pastry is cooked through and the fillings are set. Remove from the oven and set aside to cool.
To serve: Cook the asparagus spears in a large saucepan of salted, boiling water until tender, 2-3 minutes. Drain well and rinse under cold running water.
Turn out the tartlets from their pans and serve with the cooked asparagus spears as a garnish.