In a large sauté pan, heat half of the oil over medium heat.
Turn the heat down, add the shallot, and cook, stirring frequently to avoid browning, about 5 minutes.
Add the chicken broth, turn the heat to medium, and simmer to soften the shallot and reduce the liquid, about 10 minutes.
Add the cauliflower and cook until tender, stirring occasionally, about 5 minutes.
Stir in the parmesan and butter. Set the risotto aside.
Season the scallops with salt and pepper.
In a small sauté pan, heat the remaining oil over medium heat and sauté the scallops until just cooked through, 2 to 3 minutes per side.
To serve, divide the risotto between dinner plates, top with a tangle of frisée, and a squeeze of lemon juice. Divide the scallops among the dishes, and serve with a lemon wedge.