16yo DS invited his gf over Friday evening & she is a vegetarian. I asked DS what he wanted me to make for dinner that night & he responded with "She's a vegetarian." Now IDK what to make for her! I was going to make burgers & fries for the family but don't want to make her feel left out (or come off as rude).
We aren't vegetarian - but we do try to only eat meat 3 nights a week - so I can vouch for those Boca burgers and the like - those are ok - we like the Morningstar brand - they have basic veggie burgers or like special flavors like spicy black bean (my DH favorite) or the chicken patty ones are good too.
Since you aren't too familiar with vegetarian dishes, you could do a simple salad and spagetti and garlic bread- plain spagetti sauce and if you guys do meatballs - just don't cook them in the sauce. It could be a more inclusive dinner for her - so she won't have to feel like you had to go all out and do something overly special for her - I know if it were me - I would feel bad if my boyfriend's mom had to go out of her way for me. It could take the pressure off of her to know she is eating "with" you guys and not something totally different.
I am sure she will be happy with whatever you have. She's probably more worried about impressing you!