Creamy Spinach over Pasta

I got this recipe from my sister Janet. At first, I wasn't terribly enthused as I'm not a big spinach fan but my partner loves the stuff. And I know I like hot spinach dip appetizers, so thought I'd give it a try... and it's great stuff. I'm posting Janet's original version, but no one in our family can look at a recipe and not do some mods so I'll add my variations, as usual.

Ingredients:

• 1 twenty ounce bag of spinach, thawed
• 2 packages Portabella mushrooms, sliced (I like the baby Portabella)
• 5 tablespoons butter
• 2 tablespoons olive oil
• 1 two cup bag of fancy Italian cheese
• 4 ounces Monterrey Jack cheese
• 1 can condensed milk
• Garlic, to taste

Preparation:

1. Prepare entire box of large shells
2. In a saucepan melt 4 oz. Monterrey Jack and 1/2 pack fancy Italian shredded cheese in 1 can of condensed milk. (Simmer over low heat, stirring frequently, until blended and smooth.)
3. In a large skillet melt 5 tbs. butter and 2 tbs olive oil. Saute 3 cloves chopped garlic for 5 min. Add 20 oz. bag of chopped frozen spinach (thawed) and 2 packages of sliced portabella mushrooms.
4. Cook--stirring another 5 min.
5. Add cheese sauce and pour over pasta.
6. Top with other half bag of Italian cheese and serve.

Variations:

• This is good stuff, but it makes a lot. Find the small size condensed milk and the rest of the ingredients are easily halved.
• Increase the garlic; I always do for just about every recipe
• Serve with garlic bread
• Add some sliced or diced chicken
• Use pepperjack cheese instead of Monterrey jack