We keep getting ants in the pantry. We have all the food sealed up really tight, but they're persistent. So far I just kill all the ones I see and then they'll be gone for a few days. Then they'll show back up.

I sealed off the molding around the pantry door where I saw they were coming from. Now they're coming out of cracks in the corner of crown molding along the ground. So I'll seal that up too.

But does this mean I probably have a mound in my wall? What's the best way to attack this?

Google Using Boric Acid to Kill Ants

It's a powder that you can mix with sugar and water or just put in the path of the ant trails and they crawl through it and carry it back to their nest and eventually it eliminates them all. We had a bad case of carpenter ants that moved into a wall of our house after their tree was cut down. I used all kinds of stuff until I found a video on boric acid to kill carpenter ants and tried it out. It worked like a charm!

This or something similar will knock them out in a few days.

https://www.homedepot.com/p/Terro-Outdoor-Liquid-Ant-Stake-T1812/204661245

The Terro products - liquid ant bait - work really well for ants in the kitchen.

spray demon WP around the perimeter

+1 on the Terro ant baits inside until they stop coming after the bait. Then spray the perimeter to try and keep them from reappearing. Have had this issue in several places around our kitchen and would go back to the Terro anytime they got back inside.

https://www.homedepot.com/p/Terro-Liquid-Ant-Killer-Bait-Stations-6-Pack-T300/202532940

This. Had carpenter ants, made the mistake of spraying perimeter spray before dealing with them and it caused the problem to get substantially worse, not better. Kill them first, then if you feel inclined spray the perimeter.

These traps took a pretty substantial problem and got rid of it in about 4 days.