Add 1/2 cup butter 1/4 cup of Rosemary, 1/4 cup thyme, and 1/4 cup oregano, along with 5 garlic cloves in a food processor, blend until compound butter is soft
Step 3
Cut 2 yellow onions in half, place in roasting pan face down to hold up rib roast. cut up celery and carrots and herbs and put in. add rest of garlic inside and fill with beef stock until onions are covered
Step 4
Lather prime rib roast with compound butter until fully covered, place on top of onions so it is barely touching the beef stock
Step 5
Place in oven and cook for 5 min for every pound (5lb=25 min) after time is up turn off the oven and let roast sit in oven for 2 hours undisturbed, keep oven door closed
Step 6
30 minutes before oven roast is done Slice 2 yellow onions and 2 red onions. Melt 1 cup butter then add onions, salt and pepper and caramelize until brown. Then add Worcestershire sauce and red wine and cook until darker brown
Step 7
After 2 hours is up take the roast out of the oven. Turn the oven back on to 350°F. Then after taking the meat out add remaining beef stock and bring to a boil, let it cool then strain the beef stock and this will be your dip
Step 8
Using the garlic heads you roasted, bring it to a mush then add salt, pepper, mayonnaise, prepared horseradish, and drizzle a small amount of Worcestershire sauce and mix
Step 9
Take your French bread and cut it in half, add horseradish mayonnaise on top and bottom slices of bread, add meat cut into thinly sliced pieces, then add caramelized onions on tip and then 2-3 slices of Swiss cheese, place in broiling oven to melt cheese and toast bread
