In a large sturdy pot, preferably a Dutch oven, warm the olive oil over medium-high heat.
2 tbsp olive oil
Add the sausages and cook until browned, about 12 to 15 minutes, stirring frequently.
2 lbs kielbasa
Transfer kielbasa to a plate and set aside.
Add the onion and bell pepper to the pot and reduce the heat to medium. Cook until tender, about 5 minutes.
1 large yellow onion, 1 large red bell pepper
Add the flour and cook, stirring, for 2 to 3 minutes.
2 tbsp all-purpose flour
Whisk in the ale and cider and then add the thyme, stock, salt, and pepper, continuing to whisk until blended.
1 cup ale, ½ cup apple cider, 2 tbsp thyme, 1½ cups chicken stock, 1 tsp Kosher salt, ½ tsp black pepper
Bring the mixture to a boil.
Return the sausages to the pot and cover, while reducing the heat to medium-low.
Cook for 15 minutes.
Uncover and continue cooking for another 5 minutes, allowing the sauce to slightly thicken.
Serve at once with mashed potatoes on the side.
Mashed potatoes