Combine porcini mushrooms and water in a small bowl and loosely cover. Let stand for 15 to 20 minutes. Line a fine mesh strainer with a coffee filter or double layer of cheesecloth and strain the mushroom liquid into a bowl and set aside. Rinse the mushrooms, tamp them dry, and finely chop.
Meanwhile, in a small saucepan, bring the broth to a very low simmer and adjust the heat to keep it there. Add the mushroom broth when it’s ready.
In a large wide-bottomed pan such as a Dutch oven, heat a thin layer of olive oil over medium-high heat. Add the onions and shallots, season lightly with salt and pepper, and cook stirring frequently until just softened, 3 to 5 minutes.
Add the mushrooms and cook, stirring frequently, until the mushrooms release their liquid and it mostly evaporates, 3 to 5 minutes. Add the garlic and cook stirring constantly for 1 more minute. Add the rice (and additional oil if needed) and stir to coat. Continue stirring for 2 minutes (you should see the rice just starting to turn translucent on the edges), then add ½ cup of the red wine, stirring until the liquid is almost absorbed.
Adjust the heat to keep the rice mixture at a simmer and add 2 ladlefuls of warm broth, stirring well. Stir the rice every few minutes until the liquid is mostly absorbed, then add another 2 ladlefuls. Repeat until the rice is plump and creamy but still al dente, 20 to 25 minutes. When the rice seems close to being done, add the last ½ cup of wine. You might not need all the broth.
Remove from heat. Stir in the cheese. Taste and add salt and pepper as needed. Spoon risotto into individual bowls and sprinkle with more cheese. Garnish with herbs as desired. Serve immediately.