As 4dogs3cats said, beagles are notorious trash-diggers. Even when I bought a trash can with one of those foot pedals you had to step on to open the bin, they managed to figure out that one of them had to stand on the lever while the other one got up on its hind legs and pulled garbage out. I now keep my trash can inside a kitchen cabinet, with the knobs of the cabinet too high for them to reach.
If your dog is ignoring you while you're telling her "no", you may need something else to grab her attention. If she's jumping on counters, move directly where she can see you and give the "No", then put her down by her collar. Regarding the can of pennies, it works on some dogs but not on others. I know it might work on one of my dogs, who is a lot more assertive and headstrong, but I know if I tried it on my other girl, who is much less so, she would just become very fearful.
However, if your dog is ignoring you and trash-digging after you've said no, for example when you're not around, this is totally normal. Dogs follow the principle that whatever gets them a reward (food, play, toys, etc) works. That's why positive reinforcement is so successful. Digging in the trash or grabbing food off counters is very self-rewarding for dogs. They dig, they get yummy stuff; they jump up on counters, they get yummy stuff.
It's really, really difficult to train out this kind of behaviour with ANY dog, let alone a hard-headed breed like the beagle, because just one mistake can ruin any training you've done. It's much easier to just manage your environment so that these things are not accessible.