Cook macaroni according to package directions; drain and set aside.

Melt one tablespoon butter in a large skillet. Add olive oil. Add onions and sugar. Cook over medium heat, stirring often, until onions turn medium brown and start to crisp, about 20 minutes. Add mushrooms midway, if desired. Add garlic five minutes before the end.

Preheat oven to 350 degrees Fahrenheit (180 degrees Celsius). Line an oven to tableware 9×13-inch pan with Gefen Parchment Paper.

Layer half each of macaroni, onion mixture, cheese (if using ricotta cheese, place small dollops over shredded cheese layer), and crumbs in that order. Repeat layers once more, using only the macaroni, onion, and cheese this time.

Whisk together the eggs, milk, and seasonings. Carefully pour over macaroni mixture. Sprinkle remaining half of crumbs over the top. Dot with tiny cubes of butter.

Bake for 45 minutes or until golden and set. If crumbs start to burn, cover top with aluminum foil or baking paper. Let sit for a few minutes before cutting and serving.