Place the squash face down on a baking sheet at roast for 25-35 minutes depending on size. The squash are easily pierced with a fork when done.
TOMATOES
If working with slicer tomatoes, dice them into ½" pieces. Be sure to get as much of the water and seeds out of the pieces as possible.
If working with cherry tomatoes, slice them in half.
Place the tomatoes on a baking sheet and roast for 20 minutes. (Try to cook with the squash if you have enough room, otherwise place foil over the squash after they are done, while the tomatoes are roasting.)
PESTO
Place basil, pine nuts, olive oil, and garlic cloves in a food processor and blend until desired texture is acheived (15 seconds or so). Taste for extra need of garlic or olive oil. Parsely can also be added to give it more depth of flavor.
PUTTING IT TOGETHER
Once the squash have been removed from oven and have had a minute to cool slightly, use a fork to scrape the flesh to make long strands.
Divide the pesto equally among the squash halves and mix it in well.
Place the roasted tomatoes on top of the pesto, squash mixture.
Garnish with parsley, pistachios (optional), or even parmesan reggiano if you can easily digest dairy.
After tomatoes are removed from oven, drain as much water from them before adding to final dish.