In a large bowl, combine the cucumber, beets, red onion, and cilantro.
In a separate bowl, whisk together the chili powder, cumin, cayenne pepper, lime juice, and olive oil.
Pour the dressing over the salad and toss to coat.
Season with salt and pepper to taste.
These are just a few ideas for cucumber and beet salads. You can customize them to your liking by adding other ingredients such as feta cheese, nuts, or seeds.