Tomato Sandwich with Homemade Mayonnaise

Name: Tomato Sandwich with Homemade Mayonnaise
Prep time: 5 min
Cook time: 2 min
Total time: 7 min
Yield: 1 servings
Cuisine: American
Ingredients: 1 large egg; 1 tbsp lemon juice, freshly squeezed; 1 tsp distilled white vinegar; 1 tsp dijon mustard; 1/2 tsp salt; 1 cup avocado oil; 1 large ripe tomato; 2 slices crusty bread; salt, to taste; freshly ground black pepper, to taste; 1 sprig fresh basil leaves

This tomato sandwich features a quick homemade mayonnaise made with an immersion blender, paired with fresh ripe tomatoes and crispy bread for a simple yet flavorful summer classic.

🌍American 🏷️Tomato sandwich 🏷️Homemade mayonnaise 🏷️Sandwich 🏷️Tomato Basil

🏷️

🏷️Summer

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cookingwithshereenonTikTok

Total

7 min

Servings

1

Difficulty

Easy

Est. Cost

$22–$36

Recipe Source

View original recipe

From TikTok · by cookingwithshereen

-0:00

cookingwithshereenonTikTok

Ingredients

1 large egg
1 tbsp lemon juice, freshly squeezed
1 tsp distilled white vinegar
1 tsp dijon mustard
1/2 tsp salt
1 cup avocado oil
1 large ripe tomato
2 slices crusty bread
salt, to taste
freshly ground black pepper, to taste
1 sprig fresh basil leaves

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Instructions

1
To make the mayonnaise, add the egg, lemon juice, white vinegar, dijon mustard, and salt to a wide-mouth jar.
2
Pour the avocado oil on top of the other ingredients.
3
Place an immersion blender at the very bottom of the jar, making sure it covers the egg yolk.
4
Blend on high speed without moving the blender. You will see the mixture at the bottom begin to emulsify and turn white.
5
Once the bottom half is emulsified, slowly tilt and lift the blender to incorporate the remaining oil until the mayonnaise is thick and creamy.
6
To prepare the sandwich, core the tomato and slice it into thick rounds.
7
Slice two pieces of crusty bread. Toast them if desired.
8
Spread a generous amount of the homemade mayonnaise on both slices of bread.
9
Layer the tomato slices on one piece of bread.
10
Season the tomatoes with salt and freshly ground black pepper.
11
Top with fresh basil leaves.
12
Place the other slice of bread on top, slice the sandwich in half, and serve immediately.

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Tips & Notes

Pro tips

Add avocado oil to the egg mixture one drop at a time for the first few tablespoons to ensure proper emulsification before increasing the pour rate.
Slice tomatoes just before assembly and pat dry with paper towels to prevent the sandwich from becoming soggy.
Use room-temperature eggs and oil for the mayonnaise; cold ingredients are more likely to break the emulsion.
Toast the crusty bread lightly to create a barrier that keeps it from absorbing moisture from the fresh tomato.

Substitutions

avocado oil → extra-virgin olive oil or light olive oil (milder flavor, slightly different richness)
lemon juice → white wine vinegar or champagne vinegar (maintains acidity, slightly different tang)
dijon mustard → whole grain mustard or yellow mustard (changes flavor intensity and texture)

Storage & make-ahead

Store homemade mayonnaise in an airtight container in the refrigerator for up to one week. Assemble the sandwich fresh just before serving to prevent sogginess.

Equipment

immersion blender

Common Questions

Can I make mayonnaise without an immersion blender?

Yes, use a whisk and bowl, adding the oil very slowly to the egg mixture while whisking constantly to emulsify. A regular blender also works but requires more careful oil addition.

Why is my homemade mayonnaise breaking or separating?

Mayonnaise breaks when oil is added too quickly or ingredients are too cold. Add oil drop by drop at first, ensure all ingredients are room temperature, and whisk constantly.

What type of tomato works best for this sandwich?

Use large, ripe, in-season tomatoes like beefsteak or heirloom varieties. They have better flavor and texture than underripe or hothouse tomatoes.

Can I make the mayonnaise ahead of time?

Yes, homemade mayonnaise keeps refrigerated for up to one week in an airtight container. Make it a day or two before serving for best flavor.

How do I prevent the bread from getting soggy?

Slice tomatoes just before assembling, pat them dry with paper towels, and apply mayonnaise to the bread as a moisture barrier between bread and tomato.