Preheat the oven to 450°F. On a cutting board, combine the garlic, orange zest, fennel seeds, and 1 tablespoon of the rosemary. Run your knife repeatedly through the mix until it begins to take on a paste-like consistency. Scoop it up into a bowl and add the olive oil. Season the pork with salt and pepper, then rub it all over with the paste. At this point, you can cook it immediately or marinate the loin for up to 4 hours in the refrigerator for a deeper flavor. Lay the pork in a roasting pan and roast for 25 to 30 minutes (depending on the thickness of the loin), until an instant-read thermometer inserted into the middle reads 150° to 155°F. Remove from the oven and allow to rest for 10 minutes before slicing. While the pork rests, combine the beans, lemon juice, and the remaining 1⁄2 tablespoon of rosemary in a saucepan and cook until warm all the way through. Season with salt and pepper. Serve slices of the pork over the beans.