Whisk together the yeast with the warm water then combine with the rest of the ingredients in a bowl fitted for your stand mixer or a regular bowl for your hand mixer.
Using your hand mixer or stand mixer with dough hook attachment(s), mix on low speed until incorporated, then on medium speed until you achieve the windowpane test. About 7-10 minutes.
Test for the windowpane by taking a small portion of dough and roll into a ball. Stretch it out gently starting in the middle into a square shape, and until the center is a thin film. If your dough easily stretches thinly without tearing and you can see the gluten strands, then the dough is ready. If it rips easily, then you need to mix more.
Cover the dough and allow to proof until double its size.
While waiting for the dough to rise prepare the ham filling. Remove the casings from the pork sausage. Cook on medium heat breaking up the sausage meat into little bits. Cook until browned then allow to cool on paper towels to soak up the excess fat.
Once the meat has cooled combine in a food processor with the rest of the ingredients except the gruyere cheese. Blend until a smooth-ish paste forms. There will be some texture and small chunks from the meat. Set aside.
Spray your 9" x 13" baking dish with pan spray. Set aside.
On a floured surface, roll out the dough into a 12" x 15" rectangle. Spread the filling evenly around the dough leaving a ½" gap along one long side then evenly sprinkle the cheese on top.
Using a pizza cutter or knife parallel to the short side, slice into 12 strips about 1¼" wide (they'll be 12" long). Starting on the side opposite the gap, tightly roll up each bun individually firmly pressing half-inch gap into itself to seal the roll, and place in the baking dish.
Cover with plastic wrap, and allow to proof until 1.25x it's size. Preheat the oven to 375℉.
Drizzle the heavy cream over the rolls, and bake for 25-30 minutes or until light golden brown. Allow to cool for about 5 minutes then brush with melted butter and top with chopped chives and flaky sea salt.
Store covered at room temperature for about 4 days.