LENTILS: what would you cook with them?

My goal, this winter, is to clear out some of the old stuff in my pantry and make room for this year’s harvest. 

I found this box of LENTILS. 
No idea why I bought them because I never cook with lentils. 

What should I make with them? 
I’d love some “tried and true” from-scratch recipes or ideas. 
Thanks,
- Debbie