Preheat oven to 400F.

Boil potato chunks in a large pan for 5 minutes, then drain.

Transfer potatoes to a large mixing bowl.

Melt butter in a saucepan over medium heat.

Add chopped onion to the melted butter and sauté until softened.

Add bacon pieces to the saucepan and cook for 5 minutes, until lightly browned.

Combine the bacon and onion mixture with the boiled potatoes in the bowl.

Stir in white wine, heavy cream, most of the grated Gruyere cheese, and a little smoked paprika.

Season with salt and pepper to taste.

Mix all ingredients together thoroughly.

Spread the mixture evenly into a large (12in long x 2in deep) buttered baking dish.

Sprinkle the remaining Gruyere cheese over the top.

Cover the baking dish with foil.

Bake for 25 minutes.

Remove the foil.

Sprinkle a little more smoked paprika over the top.

Continue baking for another 20 minutes, or until the cheese is golden brown and bubbly.