Season pork belly with La Grille Brazilian Style BBQ Seasoning. Roast at 300 degrees Fahrenheit for 3 hours with two bricks wrapped in foil on top of another sheet pan compressing it down to keep flat. Slice and sear when plating.
Place all ingredients in a bag and vacuum seal. Sous video at 185 degrees Fahrenheit for 3 hours. Puree and season.
Sauté ingredients until they begin to caramelize. Pure then place back into a clean pan and continue to slowly caramelize, carefully stirring with a rubber spatula until it thickens.
Place cauliflower soup in a bowl. Top soup with pork belly and apple butter. Garnish with melon balled apples and fennel fronds if desired.