AT LEAST 8 AND UP to 12 hours before cooking, in a heavy-bottomed medium saucepan, whisk together the polenta and boiling water. Cover and set aside (or let cool and refrigerate for up to 2 days).

When ready to cook the polenta, add another 1 ½ cups (360ml) water and ½ teaspoon of the salt and whisk to loosen the polenta. Bring to a boil over medium-high heat, whisking frequently. Once boiling, whisk constantly until the mixture thickens, 2 to 3 minutes. Reduce the heat to low, cover, and cook, stirring vigorously with a wooden spoon every few minutes, until creamy and thick, 8 to 10 minutes.

In a small bowl, whisk the miso with the hot water to dissolve. Whisk the miso mixture and 1 tablespoon of the butter into the polenta. Taste and season with more salt as needed. Cover and keep warm.

In a large skillet, combine 1 tablespoon of the butter, the olive oil, shallot, garlic, and pepper flakes and set over medium-high heat. Once the butter melts, cook, stirring frequently, until the shallots and garlic are soft, 1 to 2 minutes. Add the asparagus and peas and stir to coat.

Add 2 tablespoons water, reduce the heat to medium, cover, and cook until the asparagus is crisp-tender and the peas are cooked through, 2 to 3 minutes. Remove from the heat and stir in the sherry vinegar, remaining ½ tablespoon butter, and remaining ½ teaspoon salt.

Serve the vegetables over the polenta. If desired, top with a sprinkling of nutritional yeast or parmesan cheese.