Preheat the oven to 425 degrees then grease the inside of 6 mini tart pans.
Roll the pie crust onto a floured surface, and roll it into a thin layer.
Divide the pie crust into four pieces, and line the mini tart pans with the crust. Then roll out the leftover crust, to use it to line the remaining two pans. Poke holes in the bottom of the crust in each tart pan with a fork to help eliminate any bubbling during the pre-cook stage.
Place 1 tablespoon of olive oil into a skillet over medium-high heat, and add the chopped onion. Cook until the onion has softened and begins to become translucent.
Slice cherry tomatoes in half, and place them in the skillet with the cooked onions. Stir and cook until the tomatoes begin to blister.
Add in ½ a teaspoon of sugar to the skillet with the onions and tomatoes, and continue to cook until the sugar begins to caramelize the vegetables.
Place some of the chopped goat cheese into the bottom of each mini tart pan.
Divide the onion and tomato mixture into the mini tart pans.
Whisk together eggs, sage and salt, and pepper to taste. Just a pinch of each should do.
Pour the egg mixture evenly into the 6 mini tart pans, do not overfill.
Reduce the heat in the oven to 325 degrees, and cook the mini tarts on a cookie sheet for 30 minutes.