Asparagus Risotto Verde

Make the broth:
Put all ingredients into a saucepan and cover with 5 cups water. Bring to a simmer, then lower heat and cook 30 minutes. Strain the broth into another pan and keep warm.
Make the risotto
Bring a medium saucepan of water to a boil with 1 teaspoon salt.
Slice off the first 3 inches of the asparagus tops. Slice the remaining stalks into 1-inch lengths. Drop the tips into the boiling water and cook 1 minute. Remove with a slotted spoon to a bowl filled with ice water. Drop the chopped stalks into the boiling water and cook exactly 3 minutes. Immediately remove the stalks with a slotted spoon and put in a blender along with the parsley or spinach. Add a pinch of salt and ½ cup of the cooking water and puree until very smooth.
Heat 1 tablespoon of the butter and the olive oil in a Dutch oven or similar heavy pot over medium-high heat until the butter melts and sizzles (but doesn’t turn brown). Add the shallot and 1 teaspoon salt and cook softened, 1 minute or so. Add the rice and stir to coat with the fat until the rice begins to crackle, 1 minute.
Pour in the wine, stir it around and boil until it’s evaporated. Pour in 2 cups of the broth and bring to a steady bubble (not a violent boil) and cook until absorbed, stirring frequently for 7-10 minutes.
Add another cup of broth, another ½ teaspoon salt and continue cooking until almost absorbed. Watch carefully at this point — the rice will be nearly ready when the grains have swelled in volume and the liquid becomes thickened.
Taste the rice. It should be tender all around, and very slightly al dente at the core. Add more liquid if needed, ¼ cup at a time until you feel it’s done. There should be some thick, starchy liquid still left in the pot. You might not use all the broth.
Remove the pan from heat and stir in the reserved asparagus puree, remaining tablespoon butter and half the cheese. Stir in the lemon juice and taste the risotto for seasoning, adding more salt to taste if needed. Gently stir in the asparagus tops.
Serve in bowls, topping with some radish, watercress and fennel fronds with additional cheese on the side.