Set up two double boilers with water in the bottom pots, and pour the semisweet chocolate chips in one pot.
Pour the white chocolate chips in the second double boiler, along with the peanut butter.
Heat the double boilers over medium heat, using a separate spoon to stir each. Once the chips begin to melt, turn the heat to medium low.
Once the chips are all melted, turn the heat off and leave the pots on the hot eyes.
Stir the food coloring into the peanut butter mixture until it's a satisfactory shade of orange.
Line the casserole dish with parchment paper (I used clothespins to keep the paper in place!) and use a spatula to evenly spread the peanut butter mixture in the dish.
Drizzle the chocolate on top of the peanut butter, making swoops and swirls. Once al of the chocolate is added, use a butter knife to swirl the peanut butter and chocolate into eye catching designs, taking care not to cut the parchment paper.
Refrigerate for at least three hours. Remove from the fridge and cut into squares, by lifting out by the parchment paper and placing on a cutter board. Clean the knife in between cuts for the cleanest cuts.
Keep tiger butter refrigerated.