Chris Shepherd's Vietnamese Beef Stew

Ingredients

• 2 tablespoons unsalted butter
• 2 pounds beef chuck, cut into 1-inch cubes
• 2 yellow onions, thinly sliced
• 1 jalapeño, stemmed and sliced into rounds
• 4 whole star anise
• 2 cinnamon sticks
• ½ cup brown sugar
• ¼ cup fish sauce
• 3 cups low-sodium beef stock, preferably homemade
• 4 medium carrots, cut into 1-inch pieces
• Salt, to taste
• Baguette, toasted and sliced, for serving