Preheat your oven to 425°F and line a large rimmed baking sheet with parchment paper.
Cut the cauliflower into bite-sized florets and slice the chicken breast into 1-inch cubes.
In a large mixing bowl, whisk together the melted ghee and the buffalo hot sauce until fully combined.
Add the cauliflower and chicken to the bowl, tossing thoroughly until every piece is evenly coated in the buffalo mixture.
Spread the cauliflower and chicken in a single layer on the prepared baking sheet, ensuring they are not overcrowded.
Roast in the oven for 20 to 25 minutes, or until the chicken is cooked through and the cauliflower is tender and slightly charred.
While the bites roast, prepare the ranch dip by whisking together the Greek yogurt, dried dill, garlic powder, onion powder, sea salt, black pepper, and lemon juice in a small bowl.
Slice the celery stalk into thin sticks for a fresh crunch on the side.
Serve the hot buffalo bites immediately with the chilled ranch dip and celery sticks.