01 - Combine cream cheese, cheddar cheese, green onions, Dijon mustard, garlic powder, salt, and pepper in a medium bowl. Mix until completely smooth and well incorporated.
02 - Lay out individual ham slices on a clean, flat work surface, ensuring they are not overlapping for easy assembly.
03 - Distribute approximately 1 tablespoon of the cheese mixture evenly across the entire surface of each ham slice, extending to the edges.
04 - Position cucumber and red bell pepper strips along one short edge of each prepared ham slice, creating a neat line for rolling.
05 - Starting from the vegetable-filled edge, roll each ham slice tightly to create secure cylinders. Place seam-side down on serving plate.
06 - Slice roll ups in half for bite-sized appetizers if preferred. Serve immediately or refrigerate 30 minutes for firmer texture.