Heat a couple of tablespoons olive oil in a large skillet. Add squash, onion, garlic, and spices to the skillet, cooking and stirring for about 10 minutes (or until vegetables are tender). Remove from heat and allow to cool to room temperature in a large bowl.
Wipe out the pan. Melt a bit of butter and toast the bread cubes on each side, seasoning with additional lemon pepper seasoning if desired.
Meanwhile, in a medium bowl, whisk together eggs, cheese, sour cream, hot sauce, and mayonnaise. Fold in half of the bread cubes.
Stir the egg mixture into the squash mixture.
Scrape the squash mixture into the prepared baking dish. Top with remaining bread cubes. Sprinkle with additional cheddar if desired.
Cover and refrigerate at least 2 hours.
Preheat oven to 350.
Grease a baking dish and set aside. Bake for about 30 minutes or until browned and bubbly.