Wash and scrub potatoes. Pierce the potatoes all over with a fork or knife and then rub the potatoes with olive oil and kosher salt. Individually wrap potatoes in foil and place them on a baking sheet. Bake at 400 degrees Fahrenheit for 1 hour, or until tender in the centers when pricked with a fork. You can alternately bake potatoes in the crockpot all day.Meanwhile, heat extra virgin olive oil in a saucepan. Add the onion and garlic and saute until onion is translucent, about 3 minutes.Add half & half, chicken broth, and shredded rotisserie chicken to the pan. Simmer 10 minutes. Add the fresh basil, ¼ cup parmesan, and 1 Tbsp lemon juice. Stir until incorporated and season to taste with salt and pepper.Steam the broccoli florets in a bowl with a lid and 1 Tbsp of water, covered for 2 minutes in the microwave. Drain water, if any.Remove potatoes from the oven, remove foil, slice potatoes in half length-wise, scoop out the centers into a bowl, and return the potato skins to the baking sheet. Mash the potato centers with a fork.Add sauce and steamed broccoli to the mashed potatoes. Fill the skins, then sprinkle the tops with the remaining ¼ cup parmesan cheese. Bake for 10 minutes (still at 400 degrees Fahrenheit) switching to the broiler the last couple minutes to let the cheese brown. Serve immediately.