Prepare the Lamb

1. Season lamb pieces with salt and pepper.
2. Heat canola oil in a large Dutch oven over medium-high heat.
3. Sear the lamb pieces on all sides until browned. Remove from the pot and set aside.

2. Create the Roux

1. Melt butter in the same pot over medium heat.
2. Add flour and stir to create a roux. Cook for 2-3 minutes until it forms a paste.
3. Pour in wine or Guinness (if using) to deglaze the pot, scraping up browned bits from the bottom.

3. Sauté the Vegetables

1. Add diced onion and carrots to the pot. Season with salt and pepper.
2. Stir to coat in the roux and cook for 6-8 minutes until softened.

4. Combine Ingredients

1. Add potatoes, peas, thyme sprigs, and bay leaves.
2. Pour in stock and stir well.
3. Return the lamb and its juices to the pot.

5. Simmer the Stew

1. Reduce heat to low, cover, and simmer gently for 1 hour, stirring occasionally.
2. Avoid boiling to keep the lamb tender and vegetables intact.

6. Finish and Serve

1. Remove thyme sprigs and bay leaves.
2. Ladle stew into bowls, garnish with fresh parsley, and serve warm with crusty bread or soda bread.