Place raw cashews in a dry skillet over medium heat. Toast, stirring frequently, for about 3-4 minutes until they turn golden brown and smell nutty. Remove from heat and let cool.
While the cashews cool, chop the cucumber into bite-sized pieces, slice the radishes thin, and dice the bell pepper. Place all the chopped vegetables into a large mixing bowl.
In a small bowl, whisk together lemon juice, honey, Dijon mustard, and olive oil until the dressing is smooth and slightly frothy.
Pour the dressing over the chopped vegetables and toss gently to coat everything evenly.
Roughly chop the cooled, toasted cashews and sprinkle them over the salad.
Gently toss the salad again to distribute the nuts without breaking them, then let it sit for 5 minutes to allow flavors to meld.
Serve immediately, garnished with extra cashews if desired, and enjoy the crunchy, fresh flavors.