Air Fryer Recipe
Caramelised Onion Tartlets
Caramelised onion tartlets are a lovely little bite, with buttery, flaky pastry and the deep, sweet flavour of onions cooked down slowly.
Ingredients
- 2 large onions, thinly sliced
- 2 tablespoons of olive oil
- 1 tablespoon of balsamic vinegar
- 1 tablespoon of brown sugar
- 100g of goat cheese
- 1 sheet of puff pastry
- Salt and pepper to taste
- Fresh thyme for garnish (optional)
Method
- Warm the olive oil in a large pan over a medium heat. Add the sliced onions with a pinch of salt.
- Cook gently for about 15-20 minutes, stirring now and then, until the onions are soft and just starting to brown.
- Add the balsamic vinegar and brown sugar to the pan, stir thoroughly, and cook for a further 5-10 minutes, until the onions are sticky and deeply caramelised.
- Take off the heat and leave to cool slightly.
- Preheat your air fryer to 180°C (350°F).
- Roll out the puff pastry on a lightly floured surface, then cut it into small circles to fit your tartlet moulds or your air fryer basket.
- Put a generous spoonful of the caramelised onion mixture onto each pastry circle. Top each one with a slice of goat cheese.
- Carefully arrange the tartlets in the air fryer basket.
- Cook for 10-12 minutes, or until the pastry is golden and puffed and the cheese has melted and is bubbling.
- Finish with a sprig of fresh thyme and serve warm.
Why this works in an air fryer
Air-fryer convection drives moisture off the pastry quickly, so the butter layers steam and lift before the onion topping can make the base soggy. Pre-caramelising the onions removes water and concentrates sugars; cooling them slightly protects the pastry fat from melting too early.
Equipment notes
Assumes a 5–6 litre basket holding 4–6 small tartlets in one layer with space between them; in a single-drawer model cook in batches for best lift, while in a dual-zone air fryer use the upper/hotter zone if applicable, rotate or swap drawers halfway, and expect the lower-loaded drawer to need 1–2 minutes longer.
Common pitfalls
- Pastry looks pale and flat at 12 minutes? The onions were too wet or added hot; reduce the onion mix until sticky, cool it before topping, and give the tartlets 2–3 extra minutes at 180°C.
- Edges brown before the centre puffs? The pastry circles are too thin or too close to the heating element; cut them slightly thicker, lower to 170°C, and cook 2 minutes longer.
- Cheese slides off and leaks into the basket? The onion mound is domed too high; flatten the filling, leave a 5mm pastry rim, and use a smaller piece of goat cheese.
- Bases are greasy or limp underneath? The basket or moulds blocked airflow; use perforated silicone/metal tartlet moulds where possible and lift the tartlets onto a rack for 2 minutes after cooking.
Variations & substitutions
- Use red onions for a sweeter filling; they release more moisture, so cook the onion stage a few minutes longer until properly jammy.
- Swap goat cheese for blue cheese; it melts faster and can split, so add smaller pieces and check from minute 8.
- Use ready-rolled shortcrust instead of puff pastry; it will not rise as much and usually needs 1–2 extra minutes for a crisp base.
- Add a thin layer of fig chutney under the onions; keep it scant because extra sugar browns quickly in the air fryer.
Storage & reheating
Keep cooled tartlets in an airtight container in the fridge for up to 3 days, then reheat in the air fryer at 160°C for 4–6 minutes until the pastry crisps again.
Nutrition
Calories: 250
