For the Beet-Blood Orange Sorbet:
Preheat the oven to 160°C. Put the beets in an oven-proof dish with a lid. Add enough water to cover the lower ¼ of the beets, then cover and roast in the oven until tender, about 1 hour. Cool the beets, then peel them and remove the stem end. Weigh the beets, then purée in a blender with 150% of their weight in cold water. Mix the sucrose, glucose powder, and apple pectin together with a whisk to homogenize. Combine the water and inverted sugar simple syrup in a pot and heat to 40°C. Add the pectin mixture to the simple syrup mixture and bring to a boil, whisking to fully dissolve the sugar and hydrate the pectin. Boil for 1 minute, then strain the liquid into a container and set over an ice bath to cool.
Measure the puréed beet mixture. Add an equal weight of fresh blood orange juice, and 50% of the total weight in syrup. Blend to homogenize. Test with a refractometer, then add the syrup to achieve 29 brix. Season the sorbet base with lime juice and salt. Rest the sorbet, covered, in the refrigerator overnight. Mix again to homogenize, then adjust the sweet-sour balance with citric acid if needed. Freeze overnight in pacojet canisters. Process the sorbet base in an ice cream machine.
For the Goat's Milk Panna Cotta:
Soften the gelatin sheets in cold water with a handful of ice. Combine the cream, sucrose, and the vanilla in a large pot and bring to a boil, while stirring. Remove the cream mixture from the heat and cool to about 60°C. Drain and purge the excess water from the gelatin then add the gelatin sheets to the cream mixture, stirring until gelatin is melted. Strain into a large container. Add the goat milk and whisk well to homogenize. Cover the panna cottas and let them rest in the refrigerator overnight. The following day put 1 kilogram of the panna cotta mixture into a chilled electric mixer bowl. Whisk on medium to high speed until the panna cotta forms soft peaks, and has doubled in volume. Pour 90 grams into each serving glass, tapping the glasses down on a towel to level the panna cotta, then cover and return to the refrigerator to set, 4 hours at least.
For the Winter Orange Salad with Tarragon:
Place the water, sucrose, and glucose powder in a pot, then zest the lemon, lime, bergamot, blood oranges, cara cara oranges, and mandarin oranges into the water. Reserve the zested citrus for later use. Crush the coriander seeds with a pestle and mortar and add to the water. Crush the lemongrass stalk by tapping it with the back of a heavy knife. Cut off the stem end and top 2/3 of the lemongrass and discard. Peel the outer layer away from the remaining stalk, then cut fine slivers of the core and add to the syrup. Bring the syrup to a boil, then remove from the heat and leave to infuse for about 15 minutes. Strain the syrup through a chinois and set over an ice bath to chill. Peel and cut suprêmes from the bergamot, blood oranges, cara cara oranges, and mandarin oranges, then cut each segment into 2 to 4 pieces on a bias to make triangular jeweled pieces about the same size as a pistachio. Slice the tarragon width-wise into fine shreds and add to the citrus segments in a small bowl. Cover with the syrup and fold gently to combine. Store salad in a container in the refrigerator.
For the Frosted Pistachios:
Preheat the oven to 150°C. Put the sugar in a rondeau and add the water. Put the rondeau over a medium heat. Bring the liquid to a boil to dissolve the sugar, then cook to 160°C. Immediately add the pistachios and stir with a wooden spoon to coat the nuts with syrup. Continue stirring as the mixture warms and the nuts begin to separate, being careful to control the heat so they do not color. Continue stirring and teasing the clusters apart until the sugar begins to crystallize. Add the butter, pistachio oil, and salt, and stir to cook off the water in the butter. Empty the pot onto a silpat-lined baking sheet. Wearing latex gloves, separate any clusters into individual nuts. If necessary, put the nuts in the oven to soften the sugar. Put the separate nuts in a perforated pan and shake to sift out any small pieces of nuts or sugar that were formed. Once cooled, store the nuts in airtight containers at room temperature.
For the Beet Bubbles:
Pass the beets through a juicer. Weigh the juice, then add an equal measure of water and simple syrup. Season with lime juice and salt, then add the lecithin. Purée with a blender until homogenized, then strain and reserve chilled.
To Assemble and Serve:
Remove the panna cottas and the beet bubble liquid from the refrigerator. With an immersion blender, shear the beet liquid into a froth and allow it to drain lightly. Spoon about 40 grams of the orange salad with some of its liquid on top of the panna cotta, mostly on one side. Plate about 30 grams of the frosted pistachio on the opposite side, scattering a few over the oranges as well. Plate a small quenelle of sorbet between them. Spoon some of the beet bubbles around one side of the sorbet, then garnish with the leaves and serve immediately.