Step 1:
Heat the oil in a small skillet over medium-high heat. Cook onions for 5 minutes or until softened. Add the garlic. cook, stirring, 1 minute or until fragrant. Remove from fire. Cool for 10 minutes.
2nd step:
Meanwhile, prepare the mashed potatoes: cook the potatoes in a pot of salted boiling water for 12 to 15 minutes or until tender. drain well. Return to skillet over low heat. Add 40 g of butter and the milk. Mash it until smooth. Add the cheese. season.
Step 3:
Preheat the oven to 180°C / 160°C convection. Grease a tray 7 cm deep, 11 cm x 21 cm wide. Line the bottom and sides with parchment paper, extending the paper 3 cm above the edges of the mold. Place ground beef, peas, eggs, breadcrumbs, barbecue sauce, tomato sauce, parsley and onion mixture in a large bowl. Season with salt and pepper. Mix well until homogeneous. Pour the mixture into the prepared pan, pressing down with the back of a spoon until smooth.
The fourth step:
Bake for 25 minutes or until golden brown and almost done. We take it out of the oven. Increase the temperature to 200°C / 180°C. Pour the mashed potatoes over the meatloaf. Add some remaining butter. Bake for 20 to 25 minutes or until the potatoes are golden brown. Place the meatloaf in the skillet for 10 minutes. Lift it onto a plate. Serve it sliced with sauce.