Preheat medium saute pan over medium, add a long squeeze of olive oil, followed by onions and a pinch of salt. Stir and cook until softened, about 5min. Move onions to a bowl and set aside.
In a food processor, add breadcrumbs. Spin to break down until powdery. Add buttermilk then spin for 10 seconds or until mixture is hydrated.
Add ground meats and process to combine and break down meat, about 15sec.
Transfer meat mixture to onion bowl and add eggs, garlic, worcestershire, mustard, poultry seasoning, pepper, and salt. Mix and fold until just combined.
Shape into a loaf. I use a loaf pan to shape it, then transfer out onto a foil lined baking tray.
Refrigerate for about 10-15min while you make the glaze.
Sear meat loaf under medium-low broiler for 5-10min until beginning to take on color on top.
Add a layer of glaze and return to cook under broiler for another 3min.
When glaze gets sticky and begins to take on color, remove loaf from oven and glaze again.
Return to oven under broiler and repeat, rotating as necessary.
Glaze a third/final time then load into a 325F/160C to bake for 25-35min or until internal temp reaches 155F/70C.
For the glaze, add ingredients to small sauce pot and stir. Once meatloaf has been glazed three times and is baking, place over medium low heat to reduce by half, about 3-4min. Stir often to prevent burning.
For onion gravy, preheat saute pan over medium heat. Add butter, onion, and a pinch of salt. Sweat for about 5min to soften.
Add flour and whisk to combine and cook for 3-5min.
Whisk in 100g or about ⅓ of the beef stock. When stirred in and thickening, whisk in remaining (350g) stock and bring to a simmer.
Once simmering, add bouillon paste and soy sauce. Simmer for about 5min or until thickened and onions are fully softened.
