Preheat oven to 350F.
Spray or lightly grease an 8 x 8 baking dish. Set aside.
To roast the garlic, cut ¼ - ½ inch off the top of the garlic bulb. Place on tin foil. Drizzle with olive oil and a sprinkle of salt. Wrap tightly with foil and roast in oven on baking sheet for 50-60 minutes. Set aside and let cool.
Place croissant cubes on baking sheet. Place in 350 F oven and toast for 5 minutes. Stir pieces and toast for another 5 minutes. Remove from oven and set aside.
Remove sausage from casing and place in sauce pan over medium high heat. Break it up with a potato masher until it resembles smaller crumbles. Cook about 5 minutes and add your chopped onion. Continue to cook until sausage has browned and onion is soft.
In a second pan over medium high heat, pour a drizzle of olive oil. Add potatoes and cook, stirring for about 5-10 minutes allowing potatoes to brown slightly and crisp. Turn heat down, season with a pinch of salt and pepper and let potatoes cook for another 5-10 minutes, stirring occasionally. Pour ¼ cup of stock into the pan and place a lid on. Let steam until most of the stock has been evaporated. Remove lid and test for doneness. If needed let them cook another 5-10 minutes until soft. Remove from heat and pour into bottom of greased casserole dish.
In a medium sized bowl lightly beat your eggs. Add in milk, cream, chives and a pinch of salt and pepper.
On top of potatoes add your browned sausage and onions. Sprinkle on a little cheese and add your croissant cubes, nestling them into the potato and sausage mixture. Squeeze your roasted garlic out of the bulb and drop all over casserole. Or you could mix the garlic in with the beaten eggs. Sprinkle on tomatillos. Pour on egg mixture and let sit for about 15 minutes allowing bread to soak up some of the liquid.
Sprinkle on the rest of the grated cheese, cover with aluminum foil and place in 350 F preheated oven for 35 minutes. Carefully remove dish from the oven and aluminum foil from the top. With the back of a spoon make 3-4 indents in the bread mixture. Crack one egg at a time into a small custard dish and slowly pour one egg into each indentation. Carefully sprinkle cooked bacon around the eggs. Return dish to oven and bake another 15-20 minutes or until the egg whites are set and yolk still runny.
