The Best Homemade Lasagna Recipe! It's so delicious that I make it almost every week

Ingredients:
Olive oil.
Onion.
Garlic.
Minced meat - 600 g.
Pepper.
Celery.
Tomatoes - 200 g.
Salt.
Pepper.
Basil.
Tomato paste - 3 tbsp.
Parsley.
Butter - 20 g.
Flour - 50 g.
Milk - 500 ml.
Nutmeg.
Lasagna - 150 g.
100g Parmesan.
Bake at 180°C for 35 minutes.