Cook the broccoli for 3 mins in boiling salted water.
Drain, run under cold water until completely cooled, then set aside.
Heat the oil in a large frying pan.
Add the onion and bacon. Cook on a medium heat for about 10 mins, adding the garlic halfway through, until the bacon is crisp and the onions are soft and golden.
Add the broccoli to the pan, then toss through to coat in the oil. Cook for a couple more mins until the broccoli is completely heated through. Season with pepper, then serve immediately.