Make your guacamole in a small mixing bowl. Slice your avocados in half the long way and gently squeeze the halves as you pull them apart. Scoop out the pit and save it for later to help keep any leftover guacamole from turning an unappealing color. Scoop out the avocado flesh into your mixing bowl. Mash the avocados with the back of a fork or a potato masher.
Peel your red onion and finely chop up about 1/4 of it, until you have 1/4 cup. Transfer the chopped onions to your mixing bowl and add the hot sauce. Cut a lime in half and squeeze the juice into the bowl. Add your salt and pepper. Mix everything with a fork.
To make your toast, cut your baguette into 4.5-inch pieces, one per person. Slice the pieces in half the long way and toast the slices.
Make your eggs up to two at a time in a large skillet. (If only making one egg, an 8-inch skillet is fine.) Melt two teaspoons of butter in your pan and crack two eggs in the pan, trying not to crowd them. Lower the heat to medium and place a lid, ideally a glass one, over the eggs.
As soon as the yolks get covered with a pinkish color, they are done. It should take around 3 minutes, so check on your eggs just before the 3-minute mark if you don't have a glass lid. Transfer each cooked egg onto a piece of toast and pour the butter on top. To cook the remaining eggs, melt two more teaspoons of butter in the pan and proceed as before.
To serve, give each person a piece of toast with the egg on it and a piece of toast with guacamole spread on it. (Or spread guacamole on both slices.) Add pepper to the eggs. Taste before adding any salt to your egg, since the guacamole has salt.
Store any leftover guacamole in the refrigerator with an avocado pit in the middle, covered with plastic wrap. Use by the following day.
If only making one egg, use one teaspoon of butter in an 8-inch skillet.