Preheat oven to 350 degrees F. Line a baking sheet with parchment paper.
In a small bowl, combine sugar, water, and salt. Add the pecans to the sugar mixture and mix until all the nuts are evenly coated.
Place the nuts in the lined baking sheet and bake for 8-10 minutes until pecans are golden brown and caramelized. Remove from oven and let the nuts cool until they reach room temperature. Chop roughly and set aside.
Bring the water and salt to a boil. Add the green beans and cover the pot.
Cook beans for 5 to 6 minutes until tender but still firm. In a large bowl, have ready about 2 cups of water with ice and transfer the green beans to the ice bath right after cooking. This will stop them from continuing to cook and give a bright green color to the beans.
Heat the butter in a skillet; add the shallot and sauté for about 1 minute, until the shallots are golden brown.
Drain the beans and add to the sauté pan. Add salt and pepper, and sauté briefly. Sprinkle the chopped candied pecans and serve.