This being a royal recipe, however, there have to be more ingredients to make it extra special.
The first is the addition of vanilla paste, offering a delicate floral note which works wonderfully with earl grey tea.
The second addition, and crucial for the melt-in-the-mouth texture, is cornstarch.
According to McGrady: “The cornstarch softens the shortbread, and makes it less glutenous.
“Instead of snapping, it crumbles, and melts in your mouth.”
In this recipe, the royal chef uses a classic Scottish shortbread mould with a thistle, the emblem of Scotland.
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