Start the recipe by prepping the shrimp (thaw under cool running water, peel them, remove tails, etc.) to ensure they're ready to go for step 9.
Add the chicken broth to a fairly large saucepan/pot over high heat. Reduce the heat to low just before it boils, and keep it on low heat for the duration of the recipe. Keep your ladle handy - you'll be gradually adding the hot broth to the risotto starting in step 7.
Meanwhile, in a Dutch oven or large, deep skillet, melt half the butter over medium heat.
Add the onion and sauté until softened (about 5-7 minutes).
Add the rice and stir constantly for 2-3 minutes.
Pour in the wine and stir until the rice fully absorbs it.
Add the broth in, one ladle at a time, only adding more once the rice has absorbed it. Make sure you stir nearly constantly. Repeat this process until you've used up all the liquid and the risotto is al dente (give it a taste - it should have a little bite to it and not be too soft). Important: If the risotto is bubbling too much/seems to be cooking too rapidly, you may want to reduce the heat to medium-low. This step should be a gradual process for best results (about 25-30 minutes). If the rice is still undercooked, heat up more broth and add it gradually until desired texture is reached.
Turn the burner off and stir in the lemon juice, lemon zest, and parmesan cheese. Cover the pot and let it sit on the stove.
Melt the remaining butter in a skillet, then add the shrimp, garlic, crushed red pepper flakes, and some salt & pepper. Cook for about 2 minutes/side or until the shrimp are pink and cooked through.
Serve the risotto with the shrimp and parsley sprinkled over top of each bowl, a squeeze of lemon juice if desired, and season with salt & pepper as needed.