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Pamela Follett/Demand Media

When you cut into a cake, give your guests a surprise under the icing. Food coloring is the secret to dyeing your cake mix, and it comes in many more colors than just red, yellow and blue. Use a color mixing chart to create different colors from primary colors. For example, you can use 1 part each of blue and black to create gray. Look for specialty food colors at baking supply stores, and add them to a light-colored cake mix.

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Pamela Follett/Demand Media

Prepare the cake mix according to the package directions.

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Pamela Follett/Demand Media

Add 3 to 5 drops of food coloring to the cake mix and stir it in.

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Pamela Follett/Demand Media

Check the coloring for the desired shade and add more food coloring, if needed. The cake will bake to a lighter color than the batter. For example, if you want a light pink cake, add red coloring to a white cake batter until it turns dark pink. It may take an entire bottle of food coloring for an intense color.

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Pamela Follett/Demand Media

Bake the cake as directed.

Tip

Light or white cake mixes work best. You will not see the coloring as well if you add it to a dark chocolate cake instead of a white cake. Gel food colorings may work better for bright, intense colors.