I am trying to get back into shape and for lunch I eat ham-flavored tofu. If I plan on giving up meat for Lent, will eating ham-flavored tofu be a violation of my Lenten penance?
No. Flavorings, meat stocks, even small pieces of meat used as a condiment (e.g., bacon bits, chunks of chicken in chicken-noodle soup) do not break the requirement to abstain from meat on Lenten Fridays. And, as for voluntary Lenten penances that Catholics take up on their own, such as your desire to give up meat for all of Lent, the Church does not regulate those.
Annual Lent Fight by Jimmy Akin