1 3-lb. rabbit, cut into 6 pieces, rib cage reserved for another use (such as stock)
1 tablespoon plus 2 teaspoons kosher salt
1 750-ml bottle dry white wine
1 garlic clove, crushed
2 3-inch strips lemon zest
1 bay leaf
1/2 teaspoon whole allspice, crushed
1 cup crème fraîche
1 tablespoon Dijon mustard
Place rabbit in a medium pot; add 1 Tbsp. salt, next 5 ingredients, and water if needed so that rabbit is completely submerged. Bring liquid to a boil over medium-high heat; immediately reduce heat and gently simmer until an instant-read thermometer inserted into the thickest part of the meat registers 135°, about 20 minutes. Let rabbit cool in cooking liquid. Drain rabbit; discard liquid.
Meanwhile, whisk crème fraîche, Dijon mustard, oregano, rosemary, thyme, and black pepper in a medium bowl. Add rabbit to marinade, turning to coat well. Cover tightly with plastic wrap and chill for 24 hours.
Lightly toast fennel seeds in a small skillet over medium heat until fragrant, about 30 seconds. Grind in spice mill and transfer to a medium bowl; whisk in remaining 2 tsp. salt and flours.