Prepare Spiced Butter and Roasted Garlic (recipes follow). Meanwhile, for caramelized squash: Cut squash in half lengthwise. Remove and discard seeds. Peel squash; slice into 3/4-inch slices. Cut slices into 3/4-inch cubes. Season squash with kosher salt and white pepper. In a very large skillet, melt butter over medium heat. Add squash. Cook, stirring occasionally, 8 to 10 minutes or until browned. Cook, covered, about 5 minutes more or until just tender. Add brown sugar. Cook, stirring occasionally, about 2 minutes or until squash has caramelized but still holds its shape. Set aside at room temperature until ready to use. (You may prepare the squash up to 1 hour in advance and store, covered, at room temperature or in the refrigerator up to 24 hours.)
In a large saucepan bring chicken stock to boiling; reduce heat to a very low simmer. In a 4- to 5-quart Dutch oven, cook bacon about 5 minutes or until lightly browned. Add shallots and sorrel. Cook and stir about 3 minutes or until shallots are tender but not brown. Reduce the heat to medium low.
Using a wooden spoon, stir the rice, sage and thyme into bacon mixture. Cook, stirring frequently, for 7 to 10 minutes or until rice is coated and just starts to brown. Add wine. Bring to boiling; reduce heat. Simmer, uncovered, until wine is absorbed, stirring often. Ladle about 1 cup of the simmering stock into the rice. Cook, stirring frequently, until most of the stock is absorbed.
Continue cooking and stirring, adding another 1 cup stock only when the previous stock is absorbed. After 15 minutes begin tasting the rice. At this point, add enough of the remaining stock, about 1/4 cup at a time, until rice is firm yet cooked through, stirring frequently and adding more stock only when the previous stock is absorbed. (You may have leftover stock).
Stir in Spiced Butter and parsley. If you like, season to taste with kosher salt and white pepper. Gently fold in the caramelized squash, keeping the individual pieces as intact as possible. Serve immediately. Makes 10 to 12 servings.