what should the internal temperature of lasagna be
1 Refrigerate until use. 2  Use or freeze within 3 days of purchase. 3  Bake in a 375Â° preheated oven, uncovered, for 45-60 minutes (note: it may take longer to bake if the lasagna is cold when you put it in the oven, bring to room temperature before baking for best results). The lasagna is done when, the top begins to brown lightly, the lasagna liquids begin to bubble around the sides of the tray, and the internal temperature reaches 165Â°. 2  If the lasagna begins to brown too quickly, cover loosely with a sheet of aluminum foil until heated through.