Instructions: 

1. Pre-heat the oven to 375 degrees. Cook pasta in a large pot of boiling salted water until just tender, but still firm, stirring occasionally, about 8-10 mins. Drain and set aside.
2. Meanwhile, heat the milk in a small saucepan, but do not boil. In a large pot, melt 6 tablespoons of butter and add the gluten-free flour. Cook over low heat for 2 minutes, stirring with a whisk. Still whisking, add the hot milk and cook for an additional 1-2 minutes, until thickened and smooth. Remove from heat. Add Gruyere, cheddar, salt, pepper, and nutmeg.
3. Combine the cooked pasta and lobster, stirring well. Spray a large casserole dish (or individual dishes) with a vegetable spray. Put a small layer of pasta in the bottom and top with cheese mixture. Add another layer of noodles and more cheese. You should have 3 layers, ending with cheese.
4. Bake for approx. 45 minutes covered, and uncover for the last 15 minutes. Remove from oven, and let sit for approx. 10 minutes before serving.