Leaving out the butter creates an obvious absence of flavor. All-butter frozen puff pastry tends to taste richer and more like homemade, while pastry made with vegetable oil has a different flavor ...
Rub the flour, salt and the 40g/1½oz chilled butter together ... The block of puff pastry can at this point be kept in the fridge for a day or two, or frozen. Remove from the fridge, unwrap ...