Tri-flavour biscotti

Soften a stick of butter by leaving it out or microwaving on low power 10 to 15 seconds at a time, rotating between bursts, until soft but not melted.

Cream the butter with 270 grams of sugar in a big mixing bowl. The sugar is high for this so it will not look fluffy, but it still cuts air bubbles into the fat.

Crack in three eggs and a little splash of vanilla and beat smooth, to the point where the mixture makes ribbons.

Add 3 grams of kosher salt and about 2 grams of baking powder.

Mix in 360 grams of flour, then work in almost a whole additional cup until the dough is dry enough not to stick to you when smashed but still feels wet - around 470 to 480 grams total.

Divide the dough roughly into thirds in smaller bowls.

First third: about a quarter cup of butterscotch chips and an equal quantity of pecans, plus an extra dose of vanilla.

Second third: white chocolate chips, almonds, a big splash of almond extract and green colour; mix in a little extra flour to match the texture of the other doughs so it does not spread more in the oven.

Mix the doughs in ascending order of darkness so the colours do not pollute each other.

Third third: a couple of tablespoons of Dutch cocoa, an extra pinch of sugar, a little glug of oil against the cocoa's drying effect, peanut butter chips and whole macadamia nuts. Knead it by hand if it is dense; it should feel firmer and drier than the others.

On a parchment-lined baking sheet form each dough into a thick snake and flatten it into a long bar of even thickness, again in ascending order of darkness.

Pile toppings on - Demerara sugar and slivered almonds, pushed in a little; powdered sugar piled loose on the chocolate, not pressed in or it dissolves.

Bake at 325F convection or 350F conventional for about 45 minutes, until springy and pillowy at the centre with a firm outer shell - at half an hour they are still soft and gooey inside.

Cut as soon as they have cooled firm enough to lift off the parchment; the softer they are the cleaner the cut. Cut at an angle and as thin as will hold together.

Saw with a chef's knife wielded like a bread knife, almost no downward pressure until it bites through the outer shell, then push through.

Lay the slices on the pan touching each other - they will not spread - and bake again to dry out and go crispy. An hour fifteen in the oven in total; go by feel, not the clock, and pull them while there is a teeny bit of squish left in the centre.

Let them cool and steam out all the way, then seal them up; they keep a lot longer than other cookies.