Pat the scallops dry on paper towels.
Drizzle the scallops with a little olive oil and sprinkle them all over with sea salt, chili powder, red pepper flakes and freshly cracked black pepper. Toss to coat well.
Preheat a cast iron skillet on medium flame until hot. Add a lug of olive oil, just enough to coat the bottom and sear the garlic cloves until golden on both sides, making sure not to burn them. Remove from the pan and set aside.
Using a pair of tongues add the scallops to the hot skillet without touching each other and sear for about 45 seconds on each side until nicely golden. Do not over cook them or they will become rubbery.
Transfer the scallops to a plate and keep warm.
Take a step back and pour the rum into the pan. Use a silicone spatula to scrape all the brown bits from the bottom of the pan and pour in the orange juice. Bring to a simmer and allow the sauce to reduce by half, about a minute or so. Remove from flame and stir in the cold butter until melted.
Taste the orange sauce and adjust seasonings with more sea salt. Add the roasted garlic cloves to the sauce if desired.
Transfer the scallops back into the orange rum sauce and squeeze the lemon all over the top.
Sprinkle with the parsley, some orange zest and serve over a bed of polenta or butternut squash puree garnished with the orange slices.