Bring a large pot of salted water to a boil. Add the orzo and cook until al dente, about 5-7 minutes. Strain and set the orzo aside to cool.
Preheat the oven to 400ºF. Spread the broccoli, onion, and garlic evenly on a baking sheet. Add olive oil and salt, and toss to coat. Roast the vegetables for 15 minutes.
After 15 minutes, add the tomatoes to the pan and roast for an additional 10-15 minutes or until the broccoli begins to brown. Remove from the oven and set aside to cool for 15 minutes.
While the vegetables are roasting heat a small skillet over medium heat and toast the pinenuts until golden brown, about 3-5 minutes.
Prepare the dressing. Add the lemon juice, lemon zest, olive oil, hummus, salt, and pepper to a bowl and whisk to combine.
Add the orzo to a bowl with half of the dressing. Toss to coat.
Add the roasted vegetables, cheddar cheese, pine nuts, salt, and remaining dressing to the orzo. Toss to combine.*
Top with fresh parsley and serve immediately or transfer to the refrigerator to cool and become more flavorful.