A breadless cucumber sandwich filled with red pesto, cherry tomatoes, mozzarella and spicy sprouts.
Fresh, crunchy and light, this sandwich swaps bread for cucumber, filled with mozzarella, cherry tomatoes, spicy sprouts and red pesto. The crunch of the cucumber contrasts with the soft, milky cheese, the tangy tomato juices and the bold flavor of the pesto. It takes 5 minutes to prepare 4 sandwiches, with no cooking required. This recipe joins my collection of keto main dishes.
What is a cucumber sandwich?
In this breadless version, two cucumber halves replace the usual slices and enclose the filling; the cucumber serves as the base, the top and the main ingredient. All the prep is done with a knife just before serving: the cucumber is washed, dried, trimmed at both ends, then divided into four sections and cut lengthwise, thick enough to stay sturdy.
The red pesto forms a creamy, fragrant layer that holds the cherry tomato halves and helps keep the halved mozzarella balls in place. The spicy sprouts add volume, freshness and a peppery note. For a cucumber boat presentation, leave the cucumber open-faced, with the filling visible and doubled, without increasing the amount of cucumber.
The origins of this version
This recipe turns the cucumber sandwich into a breadless, low-carb version. The bread gives way to the vegetable itself, chosen for its freshness, firmness and how well it holds up in your hand. The aim is a fresh bite that is easy to hold and ready in very little time, somewhere between an appetizer bite and a small cold starter.
Its keto appeal comes mainly from replacing bread with cucumber, something to consider alongside your overall daily intake. Each sandwich provides 2 g of net carbs, an amount that fits into a low-carb meal depending on what else you serve. The filling combines red pesto, mozzarella, cherry tomatoes and peppery sprouts, with no cooking at all: success depends on cutting, draining and assembly.
The main ingredients
A firm cucumber with intact skin replaces the bread, adds crunch and provides structure. After washing, dry it thoroughly to prevent water from diluting the pesto; there is no need to hollow it out or remove the seeds, as the flesh contributes freshness and firmness. Four tablespoons of red pesto provide a flavorful base and help the filling adhere to the cut surface.
Four cherry tomatoes, cut in half, add juiciness, acidity and vibrant color, distributed without making everything soggy. Four mozzarella balls, cut in half, offer a soft, milky texture and some protein; drain them well after removing them from their liquid. Pesto that is too oily may drip and cause the filling to slide out.
Two handfuls of spicy sprouts add volume, freshness and a peppery kick; mixes containing radish work well, such as daikon radish. Follow the package’s instructions, especially the use-by date: raw sprouts require particular care and are not recommended for vulnerable people. Also remember to check the pesto for allergens, especially tree nuts and milk.
Technique tips and serving
Success comes down to controlling moisture and assembling a stable sandwich: a thoroughly dried cucumber, drained mozzarella, sprouts that are not waterlogged and a thick enough pesto keep the filling between the two halves. Cutting lengthwise is essential; thin rounds would make unstable bites. Spread the pesto over four halves, add the tomatoes, mozzarella and sprouts, then place the remaining halves on top without pressing too hard.
For a low-carb meal, serve these sandwiches with a Japanese cabbage salad or deviled eggs rather than bread. The more generous cucumber boat version requires recalculating the nutritional values because the filling is doubled. Assemble as close to serving time as possible, keep the components refrigerated separately beforehand, and do not heat them, as heat would soften the cucumber.
For another light sandwich to try, see my gluten-free vegetarian sandwich.
For everyday keto cooking, here are all my low-carb recipes.
Cucumber Sandwich (Keto)
Ingredients
- 1 cucumber
- 4 mini mozzarella balls
- 4 cherry tomatoes
- 4 tablespoons red pesto
- 2 handfuls spicy sprouts
Instructions
- Wash the cucumber, trim the ends and cut it into 4 equal pieces. Cut each piece in half lengthwise.1 cucumber
- Cut the cherry tomatoes and mini mozzarella balls in half.4 cherry tomatoes, 4 mini mozzarella balls
- Spread pesto over 4 cucumber pieces. Top each with 2 tomato halves and 2 mozzarella halves. Finish with the sprouts and cover with the other cucumber half.4 tablespoons red pesto, 2 handfuls spicy sprouts
- For the boats: double the amount of pesto, tomatoes, mozzarella and sprouts.
