In a large stock pot, heat the oil and butter. Add the garlic and onions; sauté till the onions are softened.
Then add the potatoes, parsnip and 3 thyme sprigs; mix well to combine and add the stock. Bring to boil, then lower heat and cook covered till the veggies are cooked well and mushy.
Once the veggies are cooked, turn off heat and allow to cool lightly before blending the whole mixture.
Return to heat and add the milk; taste and season with salt and pepper.
In another pan, add the chopped bacon and sauté on low heat till crispy. No extra oil is required as the bacon releases enough oil.
Ladle the soup into bowls and garnish with bacon, chilli oil and thyme.