Sicilian cold braised fennel

Serves 4

1 large or 2 medium heads fennel about 1+1/4 pounds
2 tablespoons unsalted butter
3 tablespoons olive oil
1 medium onion, finely chopped
1 clove garlic, minced
1/2 teaspoon salt
1/2 freshly ground black pepper
1+1/2 teaspoons anise seeds
2 cups chicken broth
1/2 teaspoon finely grated orange peel
2 tablespoons lemon juice

Trim the stems from the fennel and peel the bottoms. Chop the fronds and reserve. Cut each bulb in half from top to bottom. 
Slice each half lengthwise into four sections
Heat the butter with the oil in a medium saucepan over medium low heat. 
Add the onion, cook 1 minute. 
Add the garlic, cook 1 minute longer. 
Stir in the fennel, salt pepper, and anise seeds. 
Cook uncovered for 10 minutes., shaking pan occasionally.
Add the chicken broth and orange peel. 
Cook, covered over low heat until tender, about 20 minutes. 
With a slotted spoon, transfer the fennel to a serving dish.
Heat the cooking liquid in the saucepan to boiling. 
Boil until reduced to about 1/2 cup. 
Cool slightly and add the lemon juice.
Pour this over fennel, cool and chill for at least 3 hours before serving. 
Sprinkle with chopped fennel fronds