The flavors of this risotto are bright and clean. Substitute one cup of frozen peas if asparagus is unavailable.
In a small saucepan, combine peppers, 6 tablespoons water, and 1/4 cup chicken stock; cover and cook over medium-low heat, stirring frequently, until very soft, about 25 to 30 minutes. Remove from heat, and puree peppers with liquid in a food processor. Strain through a coarse sieve into a small bowl. Set aside.
Bring a medium saucepan of salted water to a boil, and add asparagus. Cook until bright green and still slightly crunchy, about 1 to 2 minutes. Remove with a slotted spoon, and place in an ice bath for several minutes. Drain, and set aside.
In a medium saucepan, combine remaining 4 3/4 cups chicken stock with sprigs of mint, parsley, and rosemary, and bring to a boil. Reduce the heat to low, and keep stock at a bare simmer.
Meanwhile, heat olive oil in a heavy 4-quart saucepan over medium heat. Add shallots, fennel, and garlic, and cook, stirring frequently with a wooden spoon, until very soft but not browned, about 6 minutes. Stir in rice and coriander, and cook, stirring constantly, until the edges of the rice are translucent, about 3 minutes. Add wine and lemon zest, and cook, stirring constantly, until nearly all the wine is absorbed, about 30 seconds.
Remove herb sprigs from stock with tongs or a slotted spoon. Add salt and pepper and about 1/2 cup of simmering stock to rice, and cook over medium-high heat, stirring constantly, until nearly all the stock is absorbed. Continue adding stock, about 1/2 cup at a time, stirring constantly and allowing each addition to be nearly absorbed before adding the next, until rice is creamy-looking and each grain is tender but still firm in the center. This will take about 15 to 20 minutes.
Remove the pan from heat, and stir in pepper puree, asparagus, Parmesan, 1 tablespoon chopped mint, all the chopped parsley, and lemon juice. Adjust seasoning with salt and pepper, if necessary. Divide risotto among six plates, and sprinkle with remaining tablespoon mint. Serve immediately.