In a small saucepan, gently heat ½ cup of olive oil over medium-low heat. Add 4 minced garlic cloves, a pinch of red pepper flakes, and a handful of fresh basil leaves. Allow the mixture to infuse for about 5 minutes, until fragrant but not smoking.

In a separate pan, melt 4 tablespoons of butter over medium heat. Carefully add a halved onion and sauté for about 6-8 minutes until it becomes golden brown and caramelized. Next, add one can of San Marzano tomatoes, breaking them up with a wooden spoon. Simmer for about 10-12 minutes, allowing the sauce to thicken while stirring occasionally.

Once the sauce has thickened, remove the halved onion and stir in 3 tablespoons of the infused basil oil. Taste the Bear Spaghetti sauce and adjust seasoning with salt and pepper as needed.

As the sauce simmers, bring a large pot of salted water to a rolling boil. Add 12 ounces of spaghetti and cook according to package instructions, usually about 8-10 minutes, until al dente. Drain the spaghetti, reserving a small cup of pasta water.

Add the drained spaghetti directly into the pot with the sauce, tossing gently to ensure each strand is evenly coated. If the sauce is too thick, add a splash of the reserved pasta water to achieve the desired consistency. Serve hot, garnished with fresh basil leaves and a drizzle of the remaining infused basil oil.