Place the vegetable broth in a saucepan and gently warm it over low heat; keep it at a simmer throughout the cooking process.
Clean and thinly slice the mushrooms, then set aside; this will help them release their earthy aroma and juices when sautéed.
Dice the onion finely and mince the garlic cloves, preparing both for sautéing to build a flavorful base.
Heat the olive oil in a wide sauté pan over medium heat until shimmering, releasing a fragrant aroma as it warms.
Add the diced onion to the pan and cook, stirring frequently, until it turns translucent and soft—about 3-4 minutes.
Stir in the minced garlic and cook for another 30 seconds until fragrant, being careful not to burn it.
Add the sliced mushrooms to the pan and sauté until they release their juices and turn a deep golden brown—about 5-7 minutes—stirring occasionally.
Pour in the arborio rice and stir well to coat each grain with oil and mushroom juices, cooking for about 2 minutes until the edges look translucent.
Begin adding the warm broth, about half a cup at a time, stirring constantly and waiting until it’s mostly absorbed before adding more. Repeat this process for around 20-25 minutes, until the rice is tender but still slightly al dente.
Check the texture—if the risotto is too thick or the rice needs a little more time, add a splash more broth and stir until creamy and velvety.
Remove the pan from heat, then stir in chopped fresh herbs and a squeeze of lemon juice; add a knob of butter if desired for extra richness.
Let the risotto rest for a minute or two, then give it a gentle stir to combine all flavors. Serve immediately, garnished with additional herbs if desired.
