Arròs Caldós With Chicken, Chorizo and Mushrooms

This Spanish rice dish from chef Brett Emerson of San Francisco's Contigo is just as delicious as paella and infinitely easier to make

OVER A DECADE ago, when Brett Emerson made his first trip to Spain, the notion of opening Contigo, his Spanish restaurant in San Francisco, hadn't even occurred to him. But a few weeks of exploring the country and its kitchens changed everything. "I fell in love with the food and the way of eating," he said.

For his first Slow Food Fast contribution, Mr. Emerson shares a recipe for arròs caldós (translation: soupy rice). In Spain's Valencia and Catalonia regions, this homey classic is served throughout the year with an ever-changing lineup of seasonal ingredients. Mr. Emerson's current take combines short-grain rice with crushed tomatoes, onions, mushrooms, spinach, chorizo and pulled chicken. "We call it soupy paella on our menu because it's easier for people to understand," he said. "You have to eat this with a spoon."

The tomato broth that binds everything comes together surprisingly quickly, considering its depth. "You are cooking this at a high temperature so it bubbles vigorously," Mr. Emerson said. "That is how you concentrate the flavors and break down the starch." The result has an almost creamy texture and warming notes from saffron and rosemary.

"This is easier to make than a paella, and it's no less flavorful," Mr. Emerson said. It's exactly the kind of dish that got him hooked on Spanish cooking all those years ago. "I wasn't looking for an a-ha moment, but I had one," he said. "I wanted to capture the simplicity of that food."

—Kitty Greenwald

Total Time: 40 minutes Serves: 4

2 tablespoons olive oil

½ medium onion, finely chopped

1 pinch saffron (about 10 threads)

1 teaspoon finely chopped fresh rosemary

2 cloves garlic, finely chopped

4 ounces mushrooms, cleaned and cut into bite-size pieces

2 ounces chorizo, halved lengthwise and sliced into half moons (optional)

½ cup puréed tomatoes

5-6 cups chicken stock

Salt

Meat from ½ rotisserie chicken (about 1 pound), skin discarded, torn into bite-size pieces, white and dark meat separated

1 cup short-grain rice

Zest and juice of ½ lemon

1½ cups baby spinach leaves

1. Heat oil in a heavy pot over low-medium heat. Sauté onions until translucent and soft, about 7 minutes. Stir in saffron, rosemary and garlic and cook until aromatic, 1-2 minutes. Increase heat to medium-high and stir in mushrooms and chorizo, if using. Sauté until browned, 1–2 minutes. Add tomatoes and simmer until darkened in color, about 5 minutes.

2. Increase heat to high and add stock to pot. Bring to a vigorous boil and season with salt. Stir in dark chicken meat and rice. Boil, stirring occasionally, 10 minutes.

3. Stir in white chicken meat and lemon zest. Cook until rice is al dente, 3-5 minutes more. (Rice should be a little soupy; if it is not, add a few splashes of stock.) Stir in spinach and cook until wilted, about 2 minutes. Turn off heat and season with lemon juice and salt to taste.