3. Step
Heat oil in the pot over medium heat. Add carrots, celery, onion and garlic and cook until beginning to soften, about 5 minutes. Add chicken and cook until no longer pink on the outside, 5 to 7 minutes. Whisk cornstarch and milk in a medium bowl; add to the pot along with salt. Bring to a boil over medium-high heat, stirring often, until bubbling and thick enough to coat the back of a spoon, about 4 minutes. Remove from the heat and stir in hot sauce.