Yes. Just got back from Las Vegas on Sun Country last weekend.
We had a hot breakfast sandwich on our morning flight out and a hamburger sandwich on our late night flight back. Also got a cookie.
It's not a lot of food, and it's certainly not gourmet food, but it's more than you get on most other airlines. Think slightly better than McDonald's and you'll be in the ball park.
FWIW, I love the service on SC and for those who fly out of MSP, the HH terminal is so much nicer, faster and easier to use.