For the salad: Heat a medium saucepan over medium heat. Add 2 tablespoons olive oil and the shallot. Cook, stirring with a wooden spoon, until the shallot is fragrant and soft, about 1 minute. Add the farro and thyme and toast for another 2 minutes. Add 1/2 teaspoon salt and 2 1/2 cups water and bring to a simmer, stirring occasionally. Reduce the heat to maintain a gentle simmer. Simmer, stirring occasionally, until the water is evaporated and the farro is tender, 35 to 40 minutes. Remove from the heat, cover and let steam for 10 minutes. Discard the thyme sprigs.
Meanwhile, heat a medium skillet over medium-high heat. Add the remaining 2 tablespoons olive oil and the mushrooms. Season with the remaining 1/2 teaspoon salt and cook, stirring occasionally, until the mushrooms have lost their water and are golden brown and starting to crisp, about 15 minutes.
For the dressing: In a large bowl, make the dressing by whisking together the vinegar, olive oil, mustard, salt and thyme. Add the warm farro and mushrooms to the dressing. Toss well to coat and allow to cool to room temperature.
Add the grapes, kale and lemon juice. Toss well, top with the Gorgonzola shavings and serve.
To shave the Gorgonzola dolce, freeze it for 3 hours before. Use a vegetable peeler to shave strips.