Heat that olive oil in a heavy-bottomed pot over medium heat until it’s shimmering. Toss in your diced onion and let ’em cook for about 5-7 minutes, giving ’em a stir now and then, until they’re translucent and getting golden around the edges. Don’t cut corners here – this is where all that killer flavor starts building.

Throw in the minced garlic and red pepper flakes (if you’re using ’em) and cook for another 30-60 seconds until you can smell that amazing aroma. Keep an eye on it though – burnt garlic is nasty and will totally wreck your sauce.

Dump in those hand-squished tomatoes with all their juices. And yeah, I’m dead serious about squishing them by hand – it’s messy as hell but gives you that perfect chunky texture that makes the sauce pop. Mix in the tomato paste and give everything a good stir.

Chuck in the oregano, bay leaves, rosemary sprig, salt, and pepper. Mix it all up and bring it to a gentle bubble. Now here’s where you gotta chill – turn the heat down low, partially cover it (leave a crack for steam), and let that bad boy simmer for at least 30-40 minutes. Honestly, if you’ve got time to kill, go for a full hour. The longer it simmers, the more ridiculously good it gets.

About 5 minutes before you call it done, give it a taste. Need more salt? Throw it in. Sauce too acidic? A pinch of sugar fixes that right up. Feeling fancy? Toss in that tablespoon of butter – it makes the sauce silky smooth and is 100% worth the extra calories. Fish out the bay leaves and rosemary stem, then stir in those torn basil leaves.

Boom – your sauce is ready to rock! Slather it on pasta, pizza, or use it for dunking garlic bread. Not using it right away? Let it cool down, then stick it in containers. It’ll stay good in the fridge for about 5 days or in the freezer for a solid 3 months.