Make the dressing: Add the cilantro, sour cream, mayonnaise, lemon juice, garlic, nutritional yeast, chives, and water to a blender and blend until smooth. Season with salt and pepper to taste.
Assemble the salad: In a large bowl, combine the romaine, red onion, cucumber, jalapeño, cherry tomatoes, baby corn, mango, and avocado. Drizzle the cilantro dressing over the salad and toss until evenly coated.
Divide the salad between 4 serving bowls and top with the shrimp, feta, and chives. Season with salt and pepper.
Any leftover salad will keep in an airtight container in the refrigerator for up to 1 day.