Simmering tomato sauce with the lid on or off depends on the desired consistency of the sauce and your personal preference. Here are some guidelines:
Simmering with the lid on: If you simmer the tomato sauce with the lid on, it helps retain moisture and prevents the sauce from reducing too quickly. This method is suitable if you prefer a slightly thinner or more liquid sauce.
Simmering with the lid off: Simmering the tomato sauce with the lid off allows moisture to evaporate, which helps thicken the sauce and intensify its flavors. It can lead to a thicker and more concentrated sauce. This method is ideal if you prefer a thicker sauce or want to concentrate the flavors.
You can adjust the lid position during the cooking process as needed. If you start with the lid on to retain moisture, you can remove it later to thicken the sauce. Conversely, if the sauce becomes too thick, you can place the lid partially or fully on to add some moisture back.
Additionally, keep in mind that simmering times may vary depending on the recipe and desired flavors. It's generally recommended to simmer tomato sauce for at least 30 minutes to allow the flavors to develop, but some recipes may call for longer cooking times.
Ultimately, the decision to simmer with the lid on or off is a matter of personal preference and the desired consistency and intensity of the tomato sauce.