There would be an increase in the supply of pizzas.
Here's the reasoning: If the price of mozzarella cheese decreases due to a technological improvement in cheese production, this reduced cost for a key ingredient (mozzarella cheese) would make it cheaper for pizza producers to make pizzas. As a result, they would be able to produce more pizzas at the same price or offer pizzas at a lower price, leading to an increase in the overall supply of pizzas.