Bake the potatoes in a hot oven (200°C/350°F) for an hour or so, or until they are crisp on the outside and soft all the way through with a skewer.
When they are cool enough to handle, cut the potatoes in half and scoop out the middles. You can save this for other recipes.
Place the halves upright in a tray and drizzle with oil and sprinkle with salt, then pop them back in the oven and bake until crisp.
When they are out of the oven halve the avocados, carefully remove the stones and place a half in each potato. If they are too big you can always trim the bottoms off to make them fit more snugly in the skins.
Carefully crack eggs and separate most of the white from the yolk, then pour into the dip in the middle of the avocado halves. Sprinkle on some cheddar and then bake for 20 minutes, or until any residual egg white has cooked and the cheddar has melted. Top with slices of cooked bacon.