First, line your 8x8-inch baking pan with parchment paper, leaving some hanging over the sides to help lift the fudge out later. Crush your shortbread cookies and freeze-dried strawberries separately. Keep them in different bowls and set aside.

Get your medium saucepan and add the white chocolate chips, sweetened condensed milk, and melted butter. Put it on low heat and stir constantly until everything is melted and smooth. This usually takes about 5-7 minutes. Don't rush this part - keeping the heat low helps prevent the chocolate from burning.

Take the pan off the heat and stir in the vanilla extract and salt until well mixed. Now divide this mixture evenly between two bowls.

In one of the bowls, add your crushed freeze-dried strawberries and a few drops of pink food coloring if you're using it. Stir until well combined.

Now comes the fun part. Take both bowls and drop spoonfuls of each mixture into your lined pan, alternating between the plain white and pink strawberry mixture. Once you've used all the fudge, take a knife and gently swirl it through to create a marbled pattern. Don't overdo it - just a few swirls will look perfect.

Sprinkle your crushed shortbread cookies over the top and gently press them into the fudge. Pop the whole pan in the refrigerator and let it chill for at least 2 hours, or until the fudge is firm.

When it's completely set, lift the fudge out of the pan using the parchment paper edges. Use a sharp knife to cut it into squares. For clean cuts, wipe your knife with a warm, damp cloth between slices.

Your fudge will stay fresh in an airtight container in the fridge for up to a week. You can also freeze it for up to 3 months - just wrap it well and thaw in the fridge before eating.