Ingredients:

For Approximately 18-20 Cookies (~450g):

• 1 medium egg
• 80g powdered sugar
• 80g mayonnaise (full-fat recommended for best texture)
• 90g butter (softened at room temperature)
• ~230g flour
• 3/4 tsp baking powder (4g)
• A pinch of salt
• A pinch of vanilla extract or vanilla powder

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Step-by-Step Instructions:

Step 1: Prepare the Dough

1. Preheat the Oven:
   • Preheat your oven to 180°C (350°F) and line a baking sheet with parchment paper.
2. Cream the Butter and Powdered Sugar:
   • In a large mixing bowl, add 90g of softened butter and 80g of powdered sugar. Using a hand mixer or whisk, beat the butter and sugar together until light, fluffy, and creamy. This should take about 2-3 minutes.
3. Add the Egg and Mayonnaise:
   • Beat in 1 medium egg until well combined. Then, add 80g of mayonnaise, mixing until the batter is smooth and uniform. Mayonnaise adds moisture and softness to the cookies, so make sure it’s well incorporated.
4. Mix in the Dry Ingredients:
   • In a separate bowl, sift together 230g of flour, 3/4 teaspoon of baking powder, a pinch of salt, and a pinch of vanilla powder (or a few drops of vanilla extract).
   • Gradually add the dry ingredients to the wet mixture, stirring gently until a soft dough forms. The dough should be soft but firm enough to hold its shape when rolled into balls.

Step 2: Shape and Bake the Cookies

1. Shape the Dough:
   • Take small portions of the dough (about a tablespoon each) and roll them into balls with your hands. If the dough is too sticky, refrigerate it for 10-15 minutes to firm up.
2. Place on the Baking Sheet:
   • Place the dough balls on the prepared baking sheet, leaving about 2 inches of space between each cookie to allow for spreading during baking.
   • Gently press down on each ball with the back of a fork to create a crisscross pattern or flatten them slightly with your fingers for a more uniform shape.
3. Bake the Cookies:
   • Bake the cookies in the preheated oven at 180°C (350°F) for about 12-15 minutes, or until the edges turn a light golden brown. The centers should still be soft, as they will continue to firm up as the cookies cool.
4. Cool the Cookies:
   • Remove the cookies from the oven and allow them to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.

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Cooking Tips:

• Use Room Temperature Ingredients: Ensure the butter and eggs are at room temperature before starting. This helps in creating a smooth, evenly mixed dough.
• Avoid Overmixing: When incorporating the dry ingredients into the wet mixture, mix gently to avoid overworking the dough. Overmixing can result in tougher cookies.
• Refrigerate the Dough if Necessary: If the dough becomes too soft to handle, refrigerate it for 10-15 minutes before shaping. This will help the cookies maintain their shape during baking.
• Customize the Flavor: You can enhance the cookies by adding other flavorings like lemon zest, almond extract, or even sprinkling cinnamon or cocoa powder on top before baking.
• Storage for Better Texture: If you prefer your cookies to be softer, store them in an airtight container with a slice of bread. The bread helps keep the cookies moist.

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Storage:

• Room Temperature: Store the cookies in an airtight container at room temperature for up to 5 days. This helps them maintain their soft texture.
• Refrigeration: You can refrigerate the dough for up to 2 days if you’d like to prepare it ahead of time. Just let the dough come to room temperature before baking.
• Freezing: These cookies freeze well. After baking and cooling completely, you can freeze them in an airtight container or freezer bag for up to 3 months. Thaw the cookies at room temperature for about 20 minutes before serving.

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Nutritional Facts (per cookie, based on 18 cookies):

• Calories: 120
• Total Fat: 7g
• Saturated Fat: 4g
• Cholesterol: 25mg
• Sodium: 60mg
• Carbohydrates: 12g
• Sugar: 4g
• Protein: 2g

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Frequently Asked Questions:

1. Can I use low-fat mayonnaise?
Yes, you can use low-fat mayonnaise, but full-fat mayonnaise is recommended for the softest texture and best flavor. The fat in the mayonnaise helps make the cookies tender.

2. Can I substitute powdered sugar with granulated sugar?
Powdered sugar is used for a finer, softer texture in these cookies. Using granulated sugar may result in a slightly coarser texture, but it can be substituted in a 1:1 ratio if needed.

3. Can I add mix-ins like chocolate chips or nuts?
Absolutely! Feel free to customize the cookies by adding chocolate chips, chopped nuts, or dried fruit into the dough before baking for extra flavor and texture.

4. How can I make the cookies gluten-free?
You can substitute the all-purpose flour with a gluten-free flour blend in equal amounts. Just ensure that the blend you use contains xanthan gum or a similar binding agent to maintain the structure of the cookies.

5. How do I prevent the cookies from spreading too much?
If you notice that the cookies are spreading too much during baking, refrigerate the dough for about 15 minutes before shaping and baking. This will firm up the butter and help the cookies maintain their shape better.

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Conclusion:

Soft Mayonnaise Butter Cookies are a delightful and unique treat that will surprise you with their tenderness and buttery flavor. The mayonnaise adds an unexpected richness and moisture to the cookies, making them wonderfully soft with a melt-in-your-mouth texture. This recipe is easy to follow, quick to make, and versatile enough to be customized with your favorite flavors or mix-ins. Perfect for any occasion, these cookies are sure to be a hit with family and friends. Whether you enjoy them with a cup of tea or coffee, or as an after-dinner dessert, they will satisfy your sweet cravings with their delicious simplicity!