1. Place the eggs in a single layer in a medium saucepan; add cold water, covering the eggs by at least 1 inch (2.5 cm). Heat on high and bring the water to a boil. Cover, turn off the heat and leave alone for 12 minutes. Drain the hot water from the pot and rinse the cooked eggs under cold water for 1–2 minutes, or until they are cool enough to handle.
2. Peel the eggs and, using a sharp knife, slice in half lengthwise. Gently separate the yolks from the whites, placing them in a small mixing bowl. Arrange the whites on a plate or platter and set aside.
3. To the mixing bowl add the bacon, mayonnaise, sour cream, Dijon, lemon juice, green onion and cayenne. Mash all of the ingredients together with a fork and season well with salt and pepper.
4. Spoon the egg yolk mixture back into the egg white halves, using a spoon or a piping bag fitted with a round or star tip. Place in the fridge while you make the breadcrumb topping.
5. Melt the butter in a skillet set over medium heat and add the panko; season with salt and pepper and cook until the breadcrumbs are golden brown. Remove from heat, cool, and sprinkle over eggs just before serving.
6. Party Pointer: Feel free to make the filling and breadcrumb topping up to one day in advance. Store the filling in a lidded container in the fridge, and the topping in a lidded container at room temperature; assemble just before serving. If taking these to a potluck, take all of the components separately and assemble the deviled eggs at the party.