Add one tablespoon EACH butter and olive oil to skillet over medium heat until butter is melted. Add onion and cook until softened, about 5-7 minutes.
Stir in tomato paste and remove from heat. Allow to cool.
Add all the meatloaf ingredients (including the cooled tomato-onion mixture) to the Deluxe Stand Mixer. Using the paddle attachment, select MIX and adjust the time to 45 seconds. Press Start.
Place meatloaf into Stone Loaf Pan.
For the Glaze:
Whisk together all of the glaze ingredients until combined. Brush half of the glaze on the meatloaf.
Bake for 35 minutes; remove from oven, brush on remaining glaze.
Bake an additional 20-25 minutes, or until fully cooked to 160°F/71°C.
Notes
To freeze leftovers, slice into individual portions. Wrap in aluminum foil or place in airtight container and store up to three months in the freezer.