We are working on eating less meat these days (India really got us out of the habit) so I try to make a meatless dish about three times a week. Here is one of the ones that I like to just put together (hence the lack of amounts, just kind of use what works for your group). This is also really quick and simple.
Pasta - usually something chunky like rotini or penne, I've been into whole wheat of late
Alfredo Sauce - I usually use a jar sauce but have made a simple Parmesan cheese sauce before
When the pasta is cooking and has about five minutes left, I add the vegetables. When I think about it, I add the broccoli later because it doesn't need as much cook time as the cauliflower and carrots. Then they are already mixed together and I just have to add the sauce. If you decide not to heat up the sauce before mixing it into the pasta, then you will probably need to keep it on the stove for a bit to heat up the sauce.