We’ve been tinkering with making a frozen pizza with a par-baked crust, but the finished crust comes out chewy and bland. What’s the problem?

Pizza, as with most baked products, is always most flavorful when it comes fresh and hot out of the oven. That par-baked crust has actually been baked twice, once when it was par-baked, and the second time when it was baked as a pizza. This double baking drives off many of the desirable volatile flavors and aromas, thus reducing the overall flavor profile of the finished crust. I can’t definitively say why your crust is chewy, but if you are using a typical, high protein content pizza flour, this might explain it. To reduce the toughness/chewiness in the crust, try going to a bread flour rather than a pizza flour. This should produce a more tender eating crust characteristic. If the crust is still too tough or chewy with the lower protein bread flour, I would suggest that you increase the fat/oil content of the dough to something in the 8 to 12 percent (flour basis) range. This is commonly done when making commercial frozen pizzas as the higher fat content provides tenderness to the finished crust. It also helps to increase flavor retention in the crust, making for a better tasting crust.

We are making a par-baked pizza crust and occasionally we get opaque spots on the top of the crust that appear to be oil spots. We have reduced the oil, and adjusted the dough mixing time, but nothing seems to help. What can we do to eliminate this problem?

The problem that you are experiencing is actually due to under baking of the crust rather than poor incorporation of the oil. Those spots do look a lot like oil spots though, so I can understand how you were lead to believe that oil was the culprit.
The spots occur when portions of the crust collapse due to insufficient baking. I bet that you’ve noticed that the spots weren’t there when you took the crusts out of the oven, but they miraculously appeared — or should I say developed — shortly afterwards during cooling. To correct the problem you will need to reduce the oven temperature slightly (about 25 F) and extend the baking time by 30 to 60 seconds. Start with 30 seconds; if that doesn’t work, go to 60 seconds. If that corrects the problem, make an adjustment to the baking temperature to give you the finished crust color that you want, and you should be home free.