In a large skillet, melt butter over medium high heat. Add bay leaf, onions, shallot, then garlic. Saute for 3 minutes.
Add beef to the onion mixture and brown until mostly cooked through and in small pieces. Add coriander paste and ginger, stirring well, and let simmer a few minutes.
Add water and the tomato paste then reduce to low heat. Keep simmering until ready to plate.
Put on a large pot of water to cook dumplings. While it is rising to a boil, clean and mince/chiffonade the leeks and green onions. Reserve some green onions for garnish and combine the rest in a bowl with jalapeno, garlic, red pepper flakes, salt and pepper. Mix well.
Lay out the wonton sheets. Brush a little warm water around edges of each wrapper, portion out a teaspoon of filling per dumpling and then place another wrapper on top of each, excluding as much air as possible as you press tightly to seal. Lay out on a baking sheet.
Salt water when it has reached the boiling point then gently drop in dumplings. Cook for about 2 minutes each and then remove and drain.
Spoon a light swirl of sauce in the center of each plate then lay 2 or 3 dumplings on top. Dress with sauce. Season yogurt with salt and pepper. Place a dollop on center of each plate over dumplings. Garnish with green onions and eat.