If you are using domestic duck or goose breast, or if your wild goose breast is very fatty, score the skin side in a crosshatch pattern with your sharpest knife. You want about five to seven cuts on each angle and be sure to not cut into the meat. Skip this with a skinny goose. Salt the meat well and let them stand for 30 minutes at room temperature.
For most wild goose breasts, heat the duck fat in a large saute pan over medium-high heat and when it's hot, place the breasts skin side down. Turn the heat to medium; you want to hear a gentle sizzle, not an inferno. If you are working with very fatty breasts, turn the heat to medium and lay the goose breasts down immediately -- as the heat increases, it allows more fat to render out of the pan. Take your time with this side, which can take up to 10 minutes. When the skin is a lovely brown, flip the breasts, turn the heat up to medium-high and sear the cut side. Cook for 3 minutes, or until the meat is rare to medium. Remove and rest on a cutting board.
To make the sauce, put the shallot, chile and chopped fennel in the pan and saute for 2 to 3 minutes, stirring often. Do not let the veggies brown. Take the pan off the heat and add the ouzo. It may flame up, so be careful. Scrape any brown bits off the bottom of the pan and let the ouzo cook down by half. Add the duck stock and orange juice and a little salt and boil this furiously until a spoon passed through the sauce leaves a trail. Turn off the heat and, if you want, strain the sauce through a fine-meshed sieve to remove the solids.
Slice goose breast on the diagonal. To serve, pour a little sauce on the plate and arrange goose slices skin side up on them. Garnish with some fennel fronds and ground pepper.