- 850g large onions
Onions are endlessly versatile and an essential ingredient in countless recipes. Native to Asia…
- 3 tbsp olive oil, plus extra for greasing
Probably the most widely-used oil in cooking, olive oil is pressed from fresh olives. It's…
- 320g pack ready-rolled all-butter puff pastry
- 1 egg, beaten
The ultimate convenience food, eggs are powerhouses of nutrition, packed with protein and a…
- 2 tbsp Dijon mustard
- 25g fine breadcrumbs
- 50g grated parmesan (or vegetarian alternative)
Parmesan is a straw-coloured hard cheese with a natural yellow rind and rich, fruity flavour. It…
- ½ tsp thyme leaves
Finely slice the onions, then put them in a large, lidded pan with the oil and cook over a low heat for 30 mins, stirring from time to time.
Remove the lid and turn up the heat, cooking the onions until they brown and caramelise, stirring often.
Heat oven to 180C/160C fan/gas 4. Unroll the pastry and place on a greased baking sheet. Using a sharp knife, cut a 2cm border around the edge of the pastry, going almost but not quite through the pastry. Glaze the edge of the pastry with beaten egg.
Spread the mustard over the base of the tart and pile on the onions, spreading them out to meet the edge. Mix the breadcrumbs, Parmesan and thyme leaves together, and sprinkle this topping evenly over the onions. Bake the tart for 18-20 mins or until the pastry is golden brown.