Bring a large pot of salted water to a boil and cook the chickpea pasta according to package directions until al dente.
Reserve 0.25 cup of the pasta cooking water before draining the noodles.
While pasta cooks, dice the chicken breast into bite-sized pieces and slice the mushrooms and shallot.
Heat the olive oil in a large skillet over medium-high heat and add the chicken, seasoning with half of the salt and pepper.
Sauté the chicken for 5-6 minutes until golden and cooked through, then remove from the pan and set aside.
In the same skillet, add the sliced mushrooms and shallots, cooking until the mushrooms are browned and the shallots are translucent.
Add the minced garlic to the skillet and cook for 1 minute until fragrant.
In a small bowl, whisk together the Greek yogurt, nutritional yeast, truffle oil, and the remaining salt and pepper.
Reduce the skillet heat to low, then return the chicken to the pan along with the cooked pasta.
Stir in the yogurt mixture and the reserved pasta water, tossing everything together until a creamy sauce forms and coats the pasta.
Garnish with freshly chopped parsley and serve immediately while hot.