Cut about 1/2" off top of garlic. Cut the roots so that the garlic will sit flat. Remove the papery skin from the garlic, but leave enough that the cloves stay together. Put garlic in to a small casserole dish.

Drizzle olive oil over it an cover with lid or foil. Bake in preheated oven at 325°F for an 1hr. Remove garlic and let cook until it can be handled.

Combine water, pineapple juice, teriyaki sauce, soy sauce and brown sugar in a sauce pan over medium high heat. Stir occasionally until the mixture boils then reduce heat until mixture is just simmering.

Squeeze the sides of the head of garlic until the pasty roasted garlic is squeezed out. Measure 2 tsps into the sauce pan and whisk to combine. Add remaining ingredients to pan and stir.

Let mixture simmer for 40-50 minutes or unti lsauce has reduced by about 1/2 thick and syrupy.