I am going to guess on this one. It looks like Basil. If I could see the entire plant and if I knew what zone you are in and what type of conditions the plant is under and if the plant is an annual or a perennial that survives the winter, then perhaps I could be more accurate. One way to check on my answer is to remove a leaf and rub it between your fingers. Does it smell like basil? Please do not eat any plant that you are not sure of the identity. Basil loves heat and sunny conditions. May all your mystery plants have names, Keep growing, Marianne Binetti