Step 1

Place bacon in a single layer in the basket of an air fryer. Air-fry at 400 degrees F until the bacon is crisp, about 14 minutes, flipping once halfway through. Transfer to a paper-towel-lined plate.

Step 2

Toss Brussels sprouts, onion, oil, salt and pepper in a large bowl. Place about half of the Brussels sprouts mixture in a single layer in the air fryer basket. Air-fry at 375 degrees F until browned and crispy, 14 to 16 minutes, flipping once halfway through. Transfer to a serving platter. Repeat with the remaining Brussels sprouts mixture. Drizzle with lemon juice; sprinkle with thyme. Crumble the cooked bacon over the top.