Heat olive oil in a wide paella pan over medium heat until shimmering. Add chopped onion and minced garlic; cook, stirring occasionally, until translucent and fragrant, about 5 minutes.
Add the short-grain rice to the pan, stirring to coat each grain with oil. Toast the rice for about 2 minutes until it turns slightly translucent and smells nutty.
Sprinkle in smoked paprika and chili flakes if using, stirring quickly to evenly distribute the smoky spice throughout the rice.
Pour in the warmed vegetable broth infused with crushed saffron threads. Stir gently to distribute the rice evenly and arrange the vegetables on top.
Increase heat to high and cook for about 5 minutes, allowing the mixture to bubble vigorously and start forming a sizzle. This helps develop the crispy bottom layer.
Reduce heat to medium-low and simmer gently for 15-20 minutes without stirring, until rice is tender and the liquid has mostly absorbed. You’ll notice a golden, crispy crust forming at the bottom—this is the socarrat.
In the last few minutes, add the charred bell peppers, cherry tomatoes, artichoke hearts, and sliced mushrooms on top of the rice. Let everything cook together, allowing the flavors to meld.
Once the liquid is absorbed and rice is tender, turn off the heat. Cover the pan loosely with a clean cloth or towel and let it rest for 5 minutes to settle the flavors and enhance the crust.
Remove the cover and serve directly from the pan, ensuring you get some of that crispy socarrat on each plate. Enjoy the smoky, tender rice with charred vegetables and a vibrant aroma.
