Gather all ingredients for prep. If you use a stone heat oven to 500 degrees and get your stone good and hot. Leave in oven while preparing pizza. cook sausage until done completely. Put in a sieve and press down to remove grease.
Cook bacon how you like, I do mine in the oven on wire racks,(no grease) until crispy let cool. Slice onions 1/8 inch thick rings, set aside. Put the crust on a peel dusted with cornmeal, (slides off easier). Brush with garlic butter. Put slices of provolone on the bottom of crust. Add 1 cup of gruyere and 1 cup of fontina.
combine all ingredients for the sauce and ladle on top of cheese then add remaining cups of fontina and gruyere plus 1 cup of sharp cheddar. Scatter the italian sausage, onions and bacon over the top. Turn oven down to 450 degrees put pizza in center with rack at the middle. Bake 40- 50 minutes
Remove carefully from the oven. Let sit 10 minutes so ingredients don't run all over the place. Remember to leave a rim (crust). Also a raised rim would help hold your goodies in place. Slice and serve.
this is a fairly large pizza, but I have teenage boys that never seem to get full. Scale it back for what fits you and please enjoy.