Cheese Sauce
2 TBL butter
8 oz cream cheese
2 1/2 cups milk
2 TBL corn starch
3 oz blue cheese

Melt the butter and stir in the cream cheese in a 2 quart sauce pan. Gradually whisk in milk and corn starch. Bring to boil over medium heat, stirring constantly. Boil 1 minute. Stir in blue cheese until melted. Set aside.

Filling
2 TBL olive oil
1 cup chopped onion
1 red bell pepper
1 yellow bell pepper
8 oz mushrooms, sliced
2 cloves garlic, minced
16 oz ricotta cheese
8 oz shredded mozzarella cheese
1/2 cup grated Parmesan cheese
1 tsp salt
2 packages (10 oz each) frozen, chopped spinach, thawed and squeezed dry
8 oz lasagna noodles, cooked and drained
1/4 cup grated Parmesan cheese

Heat olive oil in a large skillet over medium heat.
Add next 5 ingredients. Sauté 8 minutes or until tender.

In large bowl combine the mozzarella, 1/2 cup Parmesan, and the ricotta cheeses plus salt. Stir in spinach and sautéd vegetables.
Pour 1 cup cheese sauce in to a 13x9x2 inch pan. Layer 1/3 of the noodles, 1/2 of the vegetable mixture, and 1 cup cheese sauce. Repeat once. Top with remaining lasagna noodles, cheese sauce, and 1/4 cup Parmesan cheese.

Bake at 350 for 55 minutes.
Remove from oven and let stand 20 minutes.