One pot balsamic beef braise - Salamanca Fresh

Ingredients

• 900g chuck or blade steak, fat trimmed, cut into 4cm pieces
• 2 tbsp plain flour
• 2 tbsp olive oil
• 1 red onion, thinly sliced
• 2 celery stalks, roughly chopped
• 3 carrots, peeled and chopped
• ¼ cup (60ml) balsamic vinegar
• ¼ cup tomato paste
• 2 tbsp brown sugar
• 1½ cups (375ml) salt-reduced beef stock
• 250g brown mushrooms, thickly sliced
• 1 bunch English spinach, trimmed and roughly chopped
• Cauliflower rice, steamed green beans, and chopped parsley, to serve