Heat the oil in a skillet over a medium heat. Add the bacon and cook through until crisp and golden. Remove from the skillet with a slotted spoon and set to one side, leaving the fat in the pan.
Step 2
Melt the butter in the skillet. Thinly slice the leeks and add to the skillet, sweating gently for a minute or so to soften, then add the kale. Season and stir to combine, cooking for a minute until the kale is just wilted.
Step 3
Roughly tear the bacon into the cooked vegetables and toss to serve.