Gluten-free creamy salmon, broccoli and penne pasta pots

Ingredients

• 20 gram butter
• 1 leek, pale section only, thinly sliced
• 2 celery stalks, finely chopped
• 1 garlic clove, finely chopped
• 200 gram broccoli, cut into florets
• 1/4 cup water
• 250 gram gluten-free penne
• 415 gram can pink salmon, drained, skin and bones removed, flaked
• 1/3 cup freshly grated parmesan
• Bechamel sauce
• 50 gram butter
• 1/3 cup gluten-free plain flour
• 1 litre reduced-fat milk
• finely grated zest and juice of 2 lemons
• 2 teaspoon fresh thyme leaves, plus extra sprigs to serve