Slow cooker pasta sauces are always a good idea, you can make bulk and freeze them or dinner is basically done after a long day at work. I picked a classic bolognese sauce and paired it with some spaghetti squash, I really loved this combo together!
For sauce: 
1lb lean ground beef
1 can tomato paste
1 container mushrooms
2 large carrots
1 medium yellow onion
4 T parsley
4 T basil
5 cloves garlic crushed
1/2 cup red wine

1-2 medium sized spaghetti squash

1. Dice veggies up into small pieces, place everything into the crock pot cook on low for 8 hours
2, Slice spaghetti squash in half, bake at 345 for 40minutes