Preheat the oven to 475°F (246°C). Place a small cooling rack on a baking sheet and lightly spray the rack with cooking spray.
Pulse the roasted salted almonds in a food processor until they become small coarse chunks; avoid processing to a fine flour so they remain crunchy.
Whisk the egg white in a small bowl. Spread the chopped almonds in a shallow plate. Season the chicken cubes with salt.
Dip each seasoned chicken cube into the egg white, shake off excess, then roll in the chopped almonds to coat evenly.
Arrange the coated chicken pieces on the prepared rack with space between them so air can circulate; sprinkle with pepper if desired.
Bake the chicken in the preheated oven until the outside is golden and crispy, about 6 minutes; flip each piece and bake an additional 4–6 minutes until cooked through and juices run clear.
While the chicken bakes, whisk together the Greek yogurt, Dijon mustard, honey, and a pinch of salt in a small bowl to make the honey-mustard dip.
Serve the almond-crusted chicken bites hot with the honey-mustard dip.