Preheat the oven to 400 degrees.
First, add the 2 Boursin cheeses to the casserole dishes.
Next, add the onions, garlic, butter, oregeno, red pepper flakes, lemon juice, oil, salt, and pepper to the casserrole dish.
Now, bake on middle rack 25 minutes.
Finally, mix together the cheesy casserole ingredients together, add 1/4 cup of pasta water, and the pasta. Enjoy!