Preheat the oven to 475°F (245°C). Place a small cooling rack on a baking sheet and lightly spray the rack with cooking spray.
Place the roasted salted almonds in a small food processor and pulse briefly until they are broken into small chunks; avoid processing into a fine flour so the coating stays crunchy.
Whisk the egg white in a small bowl. Spread the chopped almonds on a plate. Pat the chicken cubes dry and sprinkle them with a little salt.
Dip each chicken cube into the egg white, letting excess drip off, then roll the piece in the chopped almonds to coat evenly.
Arrange the coated chicken pieces on the prepared rack with space between each so air can circulate. Sprinkle with freshly ground pepper if desired.
Bake until the outside is golden brown 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 the pinch of salt in a small bowl until smooth to make the honey-mustard dip.
Serve the warm almond-crusted chicken bites with the honey-mustard dip.