Step 1. Make the 4-ingredient dressing. Add the extra-virgin olive oil, lime juice, and chili powder to a small bowl. Press or grate the garlic into the bowl. Whisk well to combine. Season with salt and pepper to taste.
Step 2. For salad jars: Add one-half of the dressing, corn, beans, banana peppers, red onion, jalapeño, tomatoes, and cilantro to 2 (32-ounce) mason jars. Cover and refrigerate for up to 4 days. Shake before serving.