Boil potatoes until soft and mash roughly. Brown onion and bacon. Allow both to cool slightly.
Combine ricotta, potatoes, bacon and onion and spices in a bowl and mix well. It is best to work in a factory mode here, so spread half the wanton wrappers on a cutting board, place filling on top, then seal each one. Here is exactly how to do it:
Spoon a heaped teaspoon of mixture into the middle of a wonton wrapper, pressing out any air out of the mixture, form a tight round. Brush edges of the pastry with water, cover with another wanton wrapper and press down around the edges firmly, making sure there is no air trapped with the filling.
Using a glass, cut the dumpling to a round shape. Press around the edges with a fork to make it look pretty and ensure the edges are sealed. Repeat with the rest.
Bring a large pot of water and 3 tsp salt to the boil. Since the stuffing is cooked, they will only need about 2 minutes to cook. Drop in 4-5 dumplings in at a time, stir gently to prevent them from sticking to the bottom and each other.
Remove with a slotted spoon and place into a large bowl sprayed with some cooking oil. Spray again over the top. Repeat with the rest.
To serve, wilt some spinach in a colander over the boiling water and arrange on the botton of a plate. Fry dumplings for a couple of minutes or until they turn golden. Melt some butter in another pan, add breadcrumbs and stir to warm though. Arrange dumplings on the plate and sprinkle with breadcrumbs.