Oysters Rockefeller Hash

Name: Oysters Rockefeller Hash
Ingredients: 1 3-ounce can smoked oysters in olive oil (such as Crown Prince brand); 3 tablespoons extra virgin olive oil, divided; 1 slice white sandwich bread; Kosher salt; Freshly ground black pepper; 3/8 teaspoon anise seeds, crushed with a mortar and pestle; 1 medium onion, diced (about 1 cup); 1 fennel bulb, cored and diced (about 1 1/2 cups); 1 pound Yukon Gold potatoes, peeled and cut into 1/2-inch dice; 2 medium garlic cloves, minced or pressed (about 2 teaspoons); 1 10-ounce package frozen chopped spinach, thawed and squeezed dry; 1 to 2 pinches cayenne pepper; 2 to 3 eggs, room temperature