Grate the potatoes and onion in a food processor using the grater attachment. Transfer to a kitchen towel over a bowl and squeeze out as much moisture as possible.
In a medium bowl, add the grated potato mixture, the chives, and the Canadian bacon. Season with salt and pepper, to taste, and mix thoroughly together.
Melt 1 tablespoon butter in a 10-inch nonstick skillet over medium heat until it just starts to foam. Add the potato mixture and using a spatula or wooden spoon, press the potatoes firmly into the bottom of the pan. Reduce heat to low and let the potatoes brown and crisp for 6 to 8 minutes.
Once brown and crisp, carefully invert the hash browns onto a rimless large plate. Add remaining tablespoon butter to pan. When butter melts, slide the hash browns back into the pan. Continue to cook over medium heat until remaining side is dark golden brown and crisp, 5 to 6 minutes longer.
Remove to a cutting board and slice into wedges. Transfer to a serving platter and garnish with chopped chives.