In a medium-size pot, cook collard greens in water (amount called for on package) and 1 tsp salt. Cook for 15 minutes, then drain and squeeze out excess moisture.
Meanwhile, in a large heavy bottomed pot bring chicken broth, half and half and garlic salt to a boil. Whisking constantly add grits in a single stream. Lower heat to medium-low and cover. Cook, stirring occasionally to prevent sticking, for 20-25 minutes or until creamy. May add more broth or half and half to thin, if needed.
After frying bacon, remove to paper towels and crumble. Cook onion in 1 Tbsp drippings until softened, about 2 minutes.
Remove grits from heat, add cream cheese and 2 Tbsp butter. Stir until fully melted. To the grits add greens, 1 cup shredded cheese, 1/2 Parmesan cheese, 1/2 cooked bacon, hot sauce and black pepper. Mix until fully combined.
To bake: Preheat oven to 350°F. Butter a 13 x 9 inch baking dish using 1 Tbsp butter or spray with cooking spray. Pour grits and greens into the dish. Top with remaining shredded cheese, Parmesan cheese and bacon. Bake for 20 minutes or until bubbly and cheese is lightly golden. May broil to brown further, if desired.
Let stand 5 minutes, garnish with green onion and serve with additional hot sauce on the side, if desired.