Season the bull tail with salt and pepper.
In a large, heavy pan (cast iron works great) heat a splash of olive oil to a medium high heat (not yet smoking).
Lightly dust the rabo de toro with flour (shake away excess) and sear each piece in the hot oil until nicely browned, about 30 seconds per side.
Remove the bull tail and let the pieces rest.
In the pan's oil, saute the leek, onion, garlic, red pepper, and tomato for about 10 minutes.
Add the carrots, bay leafs, ginger, and cloves and saute 1 minute.
Add the bull tail back to the pan and cover with the wine and stock.
Bring to a boil and then cover and reduce to a slow simmer.
Cook the rabo de toro for 3 hours and then check to see if it is falling away from the bone. It may need another hour or so if the meat is very tough.
If it is tender enough, remove the meat and then puree the sauce with a hand blender (not necessary but nice).
Serve with the sauce and homemade french fries or mashed potatoes for an authentic Spanish meal!