Drain the mushrooms, adding the broth off them to the pork broth.
Chop the mushrooms, add to put.
Wash and chop the onions, garlic, and celery and mushrooms. Add to pot.
Add the cinnamon, sage and cloves.
Take 250 ml (1 cup / 8 oz) of the reserved broth, add to pot, stir in.
Put pot over heat, bring to a boil, then reduce heat and let simmer for about 35 minutes, until only 2 or 3 tablespoons of liquid is left. (If the liquid dissolves before then and the onion is still hard, add more stock so you can simmer a bit more.)
Finally, stir in the breadcrumbs, then remove from heat.
Let cool a few minutes.
Put in a lined pie-pan.
Put top crust on; make a few slits in top crust.
Bake 35 to 45 minutes till crust is browned.
Remove from oven, let stand for about 10 minutes, then slice and serve piping hot.