Make these griddled polenta cakes with ricotta and roast peppers in two sessions, baking the polenta one night and then searing as a starter for company. Serve with lightly dressed arugula.
In a small bowl, stir the mascarpone with the heavy cream until it’s smooth. Season with salt and pepper to taste. In another bowl, toss the red pepper and onions with 2 Tbs. olive oil, the vinegar, and thyme.
Brush the slices of polenta all over with the oil. Set a 12-inch cast-iron skillet over medium heat for 2 minutes. Add half of the polenta squares, evenly spaced, and cook, undisturbed, until they brown around the edges, about 2 minutes. Flip and cook the other sides until browned, about 2 minutes. Transfer to a large platter and repeat with the remaining polenta.
To serve, spread the mascarpone on the polenta and top with the peppers and the oil-vinegar mixture. Sprinkle with pine nuts, and drizzle with the balsamic glaze.