Sauté - Heat oil in a large pot or deep skillet over medium high heat. Add onion and garlic, cook for 3 minutes or until light golden and softened.
Cook beef - Turn heat up to high and add beef. Cook, breaking it up as your go, until browned.
Reduce wine - Add red wine. Bring to simmer and cook for 1 minute, scraping the bottom of the pot, until the alcohol smell is gone.
Simmer - Add the remaining ingredients. Stir, bring to a simmer then turn down to medium so it bubbles gently. Cook for 20 - 30 minutes (no lid), adding water if the sauce gets too thick for your taste. Stir occasionally.
Slow simmer option: really takes this to another level, if you have the time! Add 3/4 cup of water, cover with lid and simmer on very low for 2 - 2.5 hours, stirring every 30 minutes or so. (Note 5) Uncover, simmer 20 minutes to thicken sauce. (Note 6 for slow cooker)
Taste and add more salt it desired. Serve over spaghetti - though if you have the time, I recommend tossing the sauce and pasta per steps below.
Bring a large pot of salted water to boil. Add pasta and cook per packet directions MINUS 1 minute.
Scoop out a mug of pasta cooking water and set aside, then drain the pasta.
Add pasta into the bolognese sauce with about 1/2 cup (125 ml) of reserved pasta water over medium heat. Toss gently for 1 1/2 - 2 minutes, or until the spaghetti turns red and the sauce thickens.
Divide between bowls. Garnish with parmesan and parsley if desired.