Remove outer leaves until heart is exposed. Peel green layer from stalk, then remove choke with a spoon and discard. Place lemon juice in a bowl and shave artichoke, using a mandolin, into bowl, tossing to coat in lemon juice and prevent discolouration, set aside.
For sour orange dressing, combine ingredients in a bowl and season to taste.
Drain artichokes of excess lemon juice, add dill and toss to combine. Pour over dressing, toss lightly, season to taste and serve immediately scattered with Manchego.