The richness of your sauce will depend on the degree of depth you roast your tomatoes, when I made this batch it ended up taking about 6 hours to “roast” three full sheet pans at 275 degrees – the oven was full! But the day before I did one tray at 275 degrees and they were done in 3 hours. So time will depend on how many tomatoes you have in your oven. You can bump the temperature up even as high as 350 but you have to really watch your tomatoes and rotate your pans from front to back and top to bottom. My favorite is when they are dark and fully roasted, sweet and thick sauce will be your reward.