Lasagna Rolls - cooking recipe

Ingredients

1 tsp. salad oil
1 medium-size onion, finely chopped
1 (28 oz.) can Italian plum tomatoes
1 (6 oz.) can tomato paste
2 tsp. sugar
1/2 tsp. Italian herb seasoning
salt
1/2 (16 oz.) pkg. curly lasagna noodles (about 9 noodles)
1 (10 oz.) pkg. frozen chopped spinach
1 (15 oz.) container reduced-fat or fat-free Ricotta cheese
2 Tbsp. grated Parmesan cheese
1/8 tsp. ground black pepper

Preparation

About 1 hour before serving: