Preheat the oven to 175°C (350°F).

Finely chop the 2 medium onions and crush the 1 garlic clove.

Heat 2 tbsp (30 ml) olive oil in the frying pan over medium-high heat.

Sauté the chopped onion until softened and lightly browned, about 8 to 10 minutes.

Transfer the sautéed onion to the medium bowl and let it cool slightly.

Heat 2 tbsp (30 ml) olive oil for tomato sauce in the same frying pan over medium heat.

Sauté the crushed garlic until fragrant, stirring constantly for about 30 seconds.

Stir 1 tbsp (15 ml) tomato paste for tomato sauce into the garlic oil for 1 minute.

Pour 1/4 cup (60 ml) white wine into the pan and stir to combine.

Add the 400 g chopped tomatoes and 1 tbsp (15 ml) ketchup to the pan.

Season the sauce with 1 tbsp dried oregano, 1/4 tsp salt, and 1/4 tsp black pepper.

Reduce the heat to low and simmer the sauce until thickened, about 15 minutes.

Place the 500 g minced beef and 500 g minced pork in the large mixing bowl.

Add the cooled sautéed onion, 1 1/2 tsp mustard powder, and 3 tsp Worcestershire sauce.

Add 1/2 cup parsley, 1 tsp fresh thyme, 1/2 tsp black pepper, and 1 tsp paprika.

Add 1 tbsp tomato paste, 1/4 cup whole milk, and the 2 large eggs.

Add 1 cup breadcrumbs and 1/2 tsp salt to the meat mixture.

Mix the meatloaf mixture thoroughly with clean hands until evenly combined.

Grease the baking pan with a little olive oil and transfer the meatloaf mixture into it.

Shape the mixture into an even log in the center of the baking pan.

Spread most of the tomato sauce over the top and sides of the meatloaf, reserving a little sauce for the potatoes.

Cut the 1 kg potatoes into approximately 3 cm pieces.

Arrange the potato pieces around the meatloaf in the baking pan.

Drizzle the potatoes with 2 tbsp olive oil for potatoes and season with 1/2 tsp salt and 1/4 tsp black pepper.

Brush the reserved tomato sauce over the potatoes.

Bake the meatloaf and potatoes at 175°C (350°F) for 60 minutes.

Remove the baking pan from the oven and loosely cover the meatloaf with aluminum foil.

Rest the covered meatloaf for 20 minutes before slicing and serving with the potatoes.