From my experience as a kosher Chef. This is quite an endeavour but not impossible. One lambs head will not provide much meat but enough for all to taste. Here is one with usage of Moroccan spices/ Sephardic flavours which go nicely with lamb and garnished with glazed apples appropriate for the holiday.
For the head;
1 whole lambs head brain removed.( note you may not need salt due to the salting of the meat when Kashered)
2 Tablespoons olive oil
2 large brown sweet onions such as vidalia cut into 8 wedges each
6 cloves garlic sliced
6 sprigs of fresh thyme
4 cups chicken stock
3 bay leaves
8 black peppercorns
4 pieces of whole clove
1 stick of cinnamon
1 tablespoon of coriander seed
1/2 cup of red wine vinegar
Set oven at 350 degrees F. Rinse head well under cold water. in a roasting pan set on top of the stove heat the oil, cook the onions until they begin to turn an amber brown. Turn off the heat and add the garlic, thyme, chicken stock, bay, clove, cinnamon,coriander seed, peppercorns and vinegar.Place the head on to the onions. cover with parchment paper and a tight fitting lid or aluminium foil securely so not to lose the liquid inside pan. Cook for 2.5 hours until cheek meat is fork tender.
For the glazed apples;
4 Granny smith green apples peeled, cored and cut into quarters
2 tablespoons demarara sugar or light brown sugar
1 tablespoon oilve oil
4 cardamom pods crushed
1 tablespoon coriander seed roughly crushed
1 star anise piece crushed
1 dried red chill such as chill di arbol crushed
1/2 cup of strained cooking liquid from the head
1/2 cup honey
Toss apple in the brown sugar to coat. In a saute pan heat oil and carefully add apples in a single layer. lightly caramelize on all sides and place in the 350 degree oven for approximately 15 minutes until apples can be pierced easily with a knife.When ready removed apples from pan and set aside. place pan back onto stove and over a medium flame. Add the crushed spices cook for a minute or two to release their flavours. then add strained cooking broth and honey Bring to a boil and lower to simmer for ten minutes or until the glaze has thickened. Remove from heat and strain over roasted apples to coat. Taste and adjust with salt black pepper and vinegar if needed. Place head onto a platter of watercress or arugula ( optional) and pour apples and glaze over the head.
Chag Sameach