A slice of savoury tart and a green salad is a perfect meal. It’s satisfying and comforting and best of all, it can be made ahead of time. 
Onions – especially sweeter red ones – are an ideal companion for pastry. 

450g small red onions 
30g unsalted butter 
1tbsp olive oil 
1tbsp balsamic vinegar 
A few sprigs of thyme 
Salt & pepper 
500g puff pastry 

Preheat the oven to 220C. 
Place a 28cm oven-proof pan on the stove. 
Put the butter and olive oil in the pan over medium heat to melt the butter. 
Meanwhile, peel the onions, slice in half through the stem end and root end. 
Slice each half into thirds, so you have six wedges per onion. 
Place the onion wedges in the pan, root end facing out, forming a circle. 
Repeat, creating an inner circle and then fill in any remaining gaps in the centre. 
The onions should fit together snugly, slightly overlapping. As they cook they’ll shrink a bit. Season with salt and pepper. 
Cook on the stove until the onions are soft. 
Sprinkle the balsamic vinegar over the onions and dot with thyme leaves. 
Remove the pan from the stove and allow to cool slightly while you roll out the pastry. 
Roll the pastry into a circle that is slightly larger than the pan. 
Tuck any excess in, to create a neat edge. 
Place the pan into the hot oven and bake until the pastry is puffed and brown. 
Remove and let the tart sit for 10-15 minutes. 
Place a cutting board that is larger than the pan, on top of the pastry and flip over so the onions are on top. 
If some of the onions stick in the pan simply lift them off and place them back onto the pastry. 
Sprinkle a few more thyme leaves on top to garnish and serve.