Should I Core tomatoes before blanching?

Chef's answer
We like to core tomatoes and scoop out most of the seeds before blanching. ... When the skin starts cracking or rippling, lift the tomato out and place in a bowl of ice water. Let the tomato chill in the ice bath for a minute or two and the skin should slip right off. Be careful because the tomato will be very hot..
Frequently asked Questions 🎓
Ah, yes, tomato ketchup has the body and robust flavor of tomato paste with a bit of added sugar and seasoning, so it makes a great substitute for tomato paste in cooking.
Can I use ketchup instead of tomato? Ketchup. This is my least favorite of the substitutions, but it works in a pinch! It's not quite as thick as tomato paste, but it's much thicker than sauce or fresh tomatoes..
Del Conte explains that "to make a good tomato sauce, you can either cook the tomatoes for a very short time or let them bubble for at least 40 minutes", because they only begin to release their acid juices after about 10 minutes, and these take at least half an hour's simmering to evaporate.
Tomato Paste: You'll just need one small can of tomato paste for this one. If you find yourself without tomato paste but your have a small can of tomato sauce, you can use that instead.
Make this Sunday sauce for your next family dinner. Make sure to let the tomato mixture cook on low heat for an hour before adding the ground beef. Then, once you add the browned beef, let the sauce cook for another hour to have all the flavors come together..
New Mexico says, "To prevent the risk of botulism, chiles and other low-acid and tomato foods not canned according to the 1994 USDA recommendations in this guide should be boiled even if no signs of spoilage are detected. ... Boiling destroys botulism toxin. If in doubt, always boil foods before tasting.".
It's not quite as thick as tomato paste, but it's much thicker than sauce or fresh tomatoes. Keep in mind that ketchup contains vinegar, sugar, and spices, so adding ketchup to your favorite recipes will certainly change their flavor profile.
A few more cooking questions 📍