Baked gnocchi parmigiana

Ingredients

• 1 kilogram potatoes, washed
• 1/4 cup freshly grated parmesan, plus 1 cup extra
• 2 teaspoons salt
• 1/2 cup plain flour
• 3/4 cup grated mozzarella cheese
• mixed salad, to serve
• Tomato sauce
• 1 tablespoon vegetable or olive oil
• 1 medium brown onion, chopped
• 2 cloves garlic, crushed
• 2 400g cans diced tomatoes
• 1 teaspoon sugar
• 1/4 cup lightly packed torn basil leaves