Heat olive oil in a large skillet over medium heat. Once heated, add the onion, carrots, and celery to the pan and sprinkle with salt. Sauté for a few minutes until softened. Add in the garlic and cook for another minute.
Add in the ground chicken and break it up into pieces. Cook until the meat is browned.
Stir in the tomato sauce and hot sauce. Turn the heat to low. Cover the pan, and let it simmer for 5 minutes.
Uncover the pan and give everything a good stir. Continue to cook, uncovered, for another couple minutes until the sauce reduces and thickens a bit. If the mixture seems dry, stir in 1/4 cup water or chicken broth. If the mixture has too much liquid, keep simmering until the sauce thickens.
Add the sloppy joe mixture to the buns, and serve with blue cheese, ranch dressing, and chives if desired.
You can swap the ground chicken for ground pork or turkey if you like.
You can use shredded rather than ground chicken for a different texture. Perfect if you have leftover roasted chicken.
The chicken mixture should be fairly thick. Let it simmer for as long as needed until you get the desired texture.