1 X 7g sachet instant dried yeast
2 pinches of caster sugar
1/3 cup (80 ml) olive oil, plus extra for brushing
450g strong flour
4 red onions, finely sliced
1 1/2 tbsp brown sugar
4 tbsp balsamic vinegar
2 tsp fennel seeds
1 X 250g punnet cherry tomatoes, halved
Combine the yeast, sugar, 2 tablespoons oil and 320 ml warm water in a bowl, then set aside in a warm place for 5 minutes or until frothy.
Sift the flour into a bowl and add 1 teaspoon salt. Make a well in the center, pour in the yeast mixture and stir to combine. Turn out onto a lightly floured surface and knead for 10 minutes or until smooth and elastic.
Place in a large bowl that has been greased with a little olive oil and cover with a damp tea towel. Set aside in a warm place for 1 hour or until doubled in size.
Meanwhile, heat the remaining oil in a frying pan over low–medium heat. Add the onion and cook, stirring, for 12–15 minutes or until soft. Add the brown sugar and vinegar and cook, stirring, for 7–10 minutes or until the onion is caramelised and the vinegar has been absorbed. Remove the pan from the heat and set aside.
Punch down the dough with your fist. Turn out onto a lightly floured surface and knead for 1–2 minutes. Spread the dough out to form a rough rectangle, then cover the surface evenly with the onion mixture. Scatter the fennel seeds on top, reserving a few to scatter over the cooked focaccia. Carefully fold the dough over on itself a few times until most of the onion mixture is incorporated into the dough (this bit can get a little sticky so ensure your work surface is well-floured).
Preheat the oven to 200°C fan-forced and grease a baking tray with olive oil. Press the dough into the prepared tray, cover with a damp tea towel and set aside in a warm, draught-free place for 20 minutes or until doubled in volume. Use your finger to press dimples into the dough, then carefully press the tomato halves into the dimples. Brush well with oil and sprinkle over the remaining fennel seeds, then season with a few good pinches of sea salt.
Bake for 20–25 minutes or until golden and cooked through. Serve warm or at room temperature.