Heat a heavy skillet over medium-high heat, add a drizzle of oil and brown the meat on all sides, seasoning with salt and pepper.
Transfer to a slow cooker and add the onion to the pan; cook for a few minutes, until turning golden. Transfer to the slow cooker.
Pour some of the stock into the skillet to loosen the flavourful browned bits in the bottom, and pour into the slow cooker with the rest of the stock.
Add the tomato paste, thyme and rosemary.
Cover and cook on low for 4 hours. Uncover, add the potatoes and carrots, cover and cook for another hour, or until the vegetables are tender.
Remove the herb stems and add salt, if needed.