Preheat oven to 180C/350F.

Heat olive oil in a deep non stick fry pan over high heat. Add onion, minced garlic and bacon. Saute for 2 to 3 minutes until onion is translucent and bacon is starting to brown.

Add chicken and cook just until the outside of the chicken turns white (do not cook through). By this time, the onion should be caramelised and bacon should be crisp.

Remove from pan onto paper towel to drain.

Lower heat to medium. Wipe pan clean and return to heat.

Melt butter, then add flour and whisk constantly for 1 1/2 minutes.

Add 1 1/2 cups of milk, whisking constantly, until it is well combined and lump free. It should be very thick.

Add remaining milk and whisk to combine well. Cook for 2 minutes or so, whisking constantly, until it thickens to the consistency of pouring cream (not whipped cream).

Remove from heat and add garlic powder, cheese, salt and pepper. Whisk until the cheese is melted and the sauce is smooth. Do a taste test and add more salt if you want.

Place broccoli in baking dish (see notes for size), then top with chicken onion mixture. Pour over half the béchamel sauce.

Top with bread cubes, then drizzle over the remaining béchamel sauce as evenly as possible over the bread cubes. Use an egg flip to squash the bread cubes down - this helps disperse the béchamel sauce throughout the bake.

Sprinkle over panko and parmesan cheese.

Place in oven and bake for 20 to 25 minutes, until golden brown.

Let stand for 5 minutes before serving. Garnish with finely chopped parsley, if desired.