This is a grilled cheese sandwich built on homemade cashew cheese, caramelized onions, and thick sourdough — cooked in vegan butter until the outside is crisp and the inside is creamy. It takes about 35 minutes and most of that is hands-off. If you’ve never made a plant-based cheese from scratch, this is a good place to start — the ingredient list is short and the blender does the work.
Why this recipe works
Two things make this sandwich actually work. First, tapioca starch in the cashew cheese creates a stretchy, slightly gooey texture when the sandwich heats through — without it, blended cashews stay dense and pasty rather than melty. Second, the onions are cooked low and slow in olive oil, which draws out their natural sugars and turns them soft and jammy. That sweetness cuts through the richness of the cashew cheese in a way that a raw or quickly sautéed onion simply won’t. Neither step is difficult, but skipping either one produces a noticeably flatter sandwich.
Mistakes to avoid
- Under-soaking the cashews. Twenty minutes in hot water is the minimum. If your blender isn’t high-speed, go 30–40 minutes. Insufficiently softened cashews leave the cheese grainy no matter how long you blend.
- Rushing the onions. Caramelized onions need at least 20–25 minutes over medium-low heat. Turning the heat up to save time gives you browned-but-bitter onions, not sweet jammy ones. Stir occasionally and be patient.
- Spreading the cheese too thick before grilling. A generous layer sounds good but the sandwich won’t heat through evenly — the bread scorches before the center warms. Aim for about a quarter-inch layer on each slice.
- Using cold vegan butter straight from the fridge. Cold butter goes into the pan unevenly and can cause hot spots that burn one corner before the rest of the bread colors. Let it sit at room temperature for a few minutes, or melt it in the pan before adding the sandwich.
- Pressing too hard with the spatula. Light pressure helps contact and browning. Mashing the sandwich flat squeezes the cheese out the sides before it has a chance to warm and set.
Leftovers and meal prep
The cashew cheese is the only component worth making ahead. It keeps in a sealed container in the fridge for up to four days and actually firms up slightly overnight, which makes it easier to spread. The caramelized onions also refrigerate well for three to four days — make a double batch and use the rest on toast or in wraps. Assembled and grilled sandwiches don’t store well; the bread goes soggy fast. If you do have a leftover half, reheat it in a dry skillet over medium-low heat for two to three minutes per side — skip the microwave, which makes the bread limp. The cashew cheese base can be frozen for up to six weeks; thaw overnight in the fridge and stir well before using.
Gourmet Vegan Grilled Cheese
Equipment
- 1 Non-stick skillet or cast-iron pan
- 1 High-speed blender
- 1 Spatula
- 1 Sharp knife
- 1 Small saucepan
Ingredients
For the Cashew Cheese
- 1 cup raw cashews soaked in hot water for 20 minutes and drained
- ¼ cup nutritional yeast
- 2 tablespoons fresh lemon juice about half a lemon
- 1 teaspoon apple cider vinegar
- ½ teaspoon sea salt adjust to taste
- ½ cup unsweetened plant milk preferably almond or oat
- 1 tablespoon tapioca starch helps with melting consistency
For the Sandwich
- 4 slices sourdough bread thick-cut, artisanal recommended
- 1 medium yellow onion thinly sliced
- 1 tablespoon olive oil for caramelizing onions
- 2 tablespoons vegan butter unsalted, for grilling sandwich
- ¼ teaspoon black pepper freshly ground
Instructions
- Prepare the Cashew CheeseIn a high-speed blender, combine the soaked and drained cashews, nutritional yeast, lemon juice, apple cider vinegar, sea salt, plant milk, and tapioca starch. Blend on high until completely smooth, scraping down sides as needed.
- Cook the Cashew CheeseTransfer the blended cheese mixture to a small saucepan over medium heat. Stir continuously for 3–5 minutes until the mixture thickens to a gooey, meltable consistency. It should stretch slightly when stirred. Remove from heat and set aside.
- Caramelize the OnionsIn a skillet over medium-low heat (135°C / 275°F), add olive oil and sliced onions. Sauté for 10–12 minutes, stirring often, until golden brown and deeply fragrant. Sprinkle with a pinch of black pepper. Set aside.
- Assemble the SandwichesSpread a generous layer of warm cashew cheese onto two slices of sourdough bread. Top each with caramelized onions, then cover with the remaining bread slices. Press slightly to secure.
- Grill the SandwichesHeat a non-stick skillet over medium heat (175°C / 350°F). Add 1 tablespoon of vegan butter. Grill each sandwich for about 4–5 minutes per side until golden brown and crispy, adding remaining butter as needed.
Notes
- Substitute tapioca starch with arrowroot if unavailable for a similar stretchy texture.
- Add a slice of tomato or a sprinkle of vegan parmesan for extra layers of flavor.
- If short on time, use pre-made vegan cheese slices, though the homemade version offers deeper flavor.
Nutrition
FAQ
Can I use store-bought vegan cheese instead of making the cashew cheese?
Yes, but the texture will be different. Most store-bought vegan slices melt adequately in a hot skillet, though they tend to be saltier and less creamy than the homemade version — taste before adding the full amount.
I don’t have a high-speed blender. Will a regular blender work?
It can work if you soak the cashews longer — closer to 40 minutes in very hot water. Stop and scrape down the sides several times during blending, and expect to blend for two to three minutes total to get a smooth result.
What can I use instead of sourdough?
Any sturdy, thick-cut bread works — a good sandwich loaf, ciabatta, or a seeded whole-grain bread all hold up to grilling. Avoid thin sandwich bread; it tends to burn before the cheese warms through.
Is nutritional yeast necessary, or can I leave it out?
It’s doing real work here — it provides the savory, slightly cheesy flavor that makes the cashew base taste like more than just blended nuts. Leaving it out produces a bland filling; it’s worth picking up at most grocery stores or online.
My cashew cheese came out too thick to spread. How do I fix it?
Add plant milk one tablespoon at a time and blend again until it loosens to a thick hummus-like consistency. The cheese also thickens as it cools, so blend it just before assembling the sandwiches.
Can I add other fillings to the sandwich?
A few thin slices of tomato or a small handful of fresh spinach both work well — add them after spreading the cheese so they don’t make the bread wet before grilling. Skip any filling with high water content like cucumber or zucchini, which will steam and soften the bread.
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- Vegan Ploughman’s Lunch Board
- BBQ Jackfruit Slider Recipe
- Smoky Vegan BBQ Sandwiches
- Vegan Chili Cheese Fries