Food & Cooking Recipes Salad Recipes Warm Spinach Salad with Shiitake Mushrooms and Red Onion By Martha Stewart Editors Martha Stewart Editors Facebook Instagram Twitter Website An article attributed to "Martha Stewart Editors" indicates when several writers and editors have contributed to an article over the years. These collaborations allow us to provide you with the most accurate, up-to-date, and comprehensive information available.The Martha Stewart team aims to teach and inspire readers daily with tested-until-perfected recipes, creative DIY projects, and elevated home and entertaining ideas. They are experts in their fields who research, create, and test the best ways to help readers design the life they want. The joy is in the doing. Editorial Guidelines Updated on February 11, 2020 Print Share Share Tweet Pin Email Photo: Paola + Murray Prep Time: 35 mins Total Time: 55 mins Yield: 10 to 12 Serves Spinach is served two ways in this salad: Sauteed with meaty shiitake mushrooms and raw. Red onions pickled in white balsamic vinegar lend brightness, while toasted sesame seeds make an unexpectedly delicious final flourish. Ingredients ½ cup white balsamic vinegar 2 teaspoons sugar Kosher salt and freshly ground pepper 1 small red onion, thinly sliced into rounds (1 cup) 2 pounds spinach (from 3 large bunches), tough stems removed, thoroughly washed and drained ½ cup extra-virgin olive oil 1 pound shiitake mushrooms, stemmed and halved, or sliced if large ¼ cup sesame seeds, toasted Directions In a saucepan, bring vinegar, sugar, and 1 teaspoon salt to a simmer. Remove from heat; stir in onion. Let cool completely. If desired, refrigerate in an airtight container up to 1 week. Drain, reserving onion and 1/3 cup liquid. Place spinach in a large bowl. In a large straight-sided skillet or shallow pot, heat 1/4 cup oil over medium-high. Add mushrooms, season with salt and pepper, and cook, stirring occasionally, until tender and golden brown in places, about 15 minutes. Add about one-quarter of spinach and cook just until collapsed, about 1 minute. Immediately spoon mushroom mixture over spinach in bowl; add reserved pickled onion and pickling liquid, remaining 1/4 cup oil, and sesame seeds. Toss to evenly coat. Season with salt and pepper; serve. Print