Set your oven to 200°C (390°F) and place the feta block in the center of a large ovenproof dish. Drizzle one tablespoon of olive oil over the cheese, then transfer it to the oven and let it roast for around 8 minutes until it starts to soften. While the feta cooks, toss the halved cherry tomatoes and cut asparagus with the remaining olive oil and some salt and pepper, then add them around the feta and roast for another 12-15 minutes until the vegetables are tender. Meanwhile, cook the orzo pasta according to package instructions until al dente, then drain. Once the vegetables and feta are ready, stir the softened feta and roasted veggies into the cooked orzo. Mix in chopped basil, fresh chives, mascarpone cheese, and baby spinach, seasoning with salt and black pepper to taste. Serve warm, garnished with extra herbs if desired.