In a large bowl, mix the flour and salt.

Add the margarine pieces and mix with your fingertips until the mixture resembles breadcrumbs.

Gradually add the cold water while mixing until the dough comes together.

Shape the dough into a ball, wrap it in plastic wrap, and let it rest in the refrigerator for 30 minutes.

Wash and drain the spinach. Heat a pan with a bit of olive oil and sauté the chopped onion until translucent.

Add the minced garlic and sauté for another minute.

Add the spinach and cook until wilted. Drain well to remove excess liquid.

In a bowl, mix the soy cream, silken tofu, nutritional yeast, chickpea flour, Dijon mustard, salt, pepper, and nutmeg. Whisk until smooth.

Add the cooked spinach and mix well.

Preheat the oven to 180°C (350°F).

Roll out the shortcrust pastry on a lightly floured surface and cut out circles to fit the mini quiche or muffin tins.

Line the tins with the pastry circles and prick the bottom with a fork.

Fill each pastry shell with the spinach filling.

Bake for about 20 to 25 minutes, until the mini quiches are golden and the filling is set.

Let the quiches cool slightly before removing them from the tins. Serve warm or at room temperature.