In a large skillet, over medium heat, add the olive oil and sausages; cook the sausages, browning on all sides, according to the package instructions; this will usually take about 10 minutes, per side, for a total of 20 minutes.
Remove the cooked sausages from the skillet; place them on a plate and set aside.
Add the onions to the hot skillet; cook for 10 minutes until they are soft and lightly browned.
Add the minced garlic; stir into the onions and cook for 2 minutes more.
Next, add the flour; stir it into the onion and garlic mixture until you can no longer see any of the flour.
Pour in the vegetable broth and use a whisk to incorporate the broth into the onions and garlic; whisking will also scrape off any brown bits in the skillet which will add flavour to the gravy.
Season with Worcestershire sauce; add color with dark soy sauce and add in the fresh thyme leaves, salt and ground black pepper; continue to whisk until the gravy comes to a boil and begins to thicken.
Reduce heat to simmer.
Add the sausages back to the skillet and coat them in the gravy; simmer for 3 to 4 minutes to fully reheat the sausages.
Serve with mashed potatoes, steamed green peas with carrots.