Preheat the oven to 390Â°F/gas 6 and line a 12 hole muffin tin with cases.
Cut the asparagus stems into small pieces, about 1cm in length, leaving the tips a little longer and blanch in boiling water for a couple of minutes. Drain and refresh under cold running water, separating the tips from the pieces of stem.
In a large bowl, mix the flour with the cubes of cheese.
Melt the butter and pour into a jug. Stir through the chives, milk, yogurt, mustard and eggs. Mix well until combined and season generously with salt & pepper.
Gently fold the wet ingredients into the flour & cheese, and stir through the asparagus stems. Be careful not to over mix and stop as soon as the mixture is combined.
Spoon the mixture evenly between the muffin cases and push an asparagus tip into the middle of each. Bake in the oven from 25-30 minutes until golden. Best eaten hot out of the oven, spread with a little cold butter.