Cookie Dough: In the large bowl of a stand mixer, cream together the butter, sugar, lime extract (or lime juice) and vanilla extract. Cream for 2 minutes on medium-high speed until fluffy and pale yellow in color.
Add the eggs one at a time beating well after each addition. Next, add the lime zest.
In a separate medium bowl, use a whisk to sift together the flour, baking soda and salt.
With the mixer on low speed gradually add the flour mixture. Stop and scrape the sides of the bowl, as needed. Beat until the dry ingredients are fully moistened.
Use a large spoon or rubber spatula to fold in the white chocolate chips and coconut by hand. Cover and chill for 30 minutes to 1 hour.
Bake: Preheat the oven to 375°F. Line 2 cookie sheets with parchment paper or a silpat baking mat.
Divide the cookie dough into mounds using a medium ice cream scoop (1 1/2 tablespoons) leaving 3-inches apart to allow for spreading.
Bake for 12-14 minutes or just until lightly golden brown in color. Cool on the pan for 3 minutes then remove to a wire rack to cool.
Store tightly sealed at room temperature for up to 4 days.
Notes
Key Lime Flavor Alternatives - When deciding which to use, lime juice or lime extract keep in mind that extract has a more concentrated lime flavor. The amount of fresh key lime zest can be increased for a more intense lime flavor, too. Lime extract is available with the other flavorings and extracts on the baking aisle of most grocery stores. Using it will give the cookies a more intense lime flavor.
Soften the Butter to Make it Easier to Cream - It's important when making these cookies to allow time for the butter to soften so that it will incorporate evenly with the granulated sugar and eggs.
Nuts - You can add 1/2-1 cup of macadamia nuts, pecans or walnuts to the cookie dough for crunch.
Coconut - Shredded coconut gives these cookies a delightfully chewy texture. You could omit it or use coconut extract instead, for a pop of coconut flavor. The texture will change, but the cookies will still be delicious.
Icing - I don't typically frost these cookies but you could, if you want. A creamy lime frosting made with powdered sugar and lime juice would be tasty!