Preheat oven to 425 degrees F. Drizzle mushrooms and tomatoes with a light coat of olive oil. Sprinkle with garlic salt and pepper. Bake for 20-25 minutes, tossing hallway through. If wanted, broil the last few minutes.
Pasta:
Bring a large pot of generously salted water to a boil over high heat. Add pasta and cook until desired tenderness, 8-12 minutes. Drain, reserving 1 cup water for later use.
Farro:
Bring 3 cups salted water to a boil over high heat, then and farro; cover and simmer (maintaining a bubbles) for 25-30 minutes or until water is absorbed. Fork fluff.
For Pesto:
In a food processor with the S blade—combine walnuts, garlic, jalapeño, half the cheese, salt, and pepper. Process for 15 seconds. Scrape the sides, then add greens. While the processer is running, slowly pour the oil and lemon juice through the feed tube and continue until blended. Add remaining cheese and capers, puree for another minute.
Toss noodles and farro with pesto. If needed, add pasta water to thin. Stir in mushroom and tomatoes. A few grates of cheese and enjoy.
Keep pesto stored separate from noodles until ready to enjoy again.
A microwave changes the structure and consistency of pesto, so to best reheat, let come to room temperature on the counter even setting by an oven or stovetop while re-heating noodles.
Stir pesto into heated noodles or grains.
If kept in an airtight container, pesto keeps in the refrigerator for up to 4-5 days.