Onion Focaccia

Dough

• 100 g milk
• 2 ½ tsp dried instant yeast
  or 25 g fresh yeast, crumbled
• 1 tsp sugar
• 50 g olive oil, plus extra for greasing
• 200 g water
• 600 g strong white bread flour, plus extra for flouring
• 1 Tbsp fine sea salt

Topping

• 45 g extra virgin olive oil, plus extra for greasing
• 50 g water
• 2 tsp fine sea salt
• 250 g white onions, sliced (3 mm)
  or 250 g red onions, sliced (3 mm)