French Onion Grilled Cheese

Name: French Onion Grilled Cheese
Prep time: 16 min
Cook time: 12 min
Total time: 29 min
Ingredients: 4 slice Sourdough, sliced; 120 g Caramelized onion, prepared; 100 g Gruyere, grated; 1 tsp Thyme, leaves only; 28 g Butter, softened; ¼ tsp Salt; ¼ tsp Black pepper, ground

French Onion Grilled Cheese · ready in 29 min · 2 servings · 590 kcal per serving · easy · 7 ingredients

French onion soup slips into a crisp sourdough sandwich with sweet onions, nutty Gruyere, thyme, and butter.

Prep: 16 min
Cook: 12 min
Total: 29 min
Serves: 2
kcal: 590
Difficulty: easy

Main dishes Quick (30 min or less)Vegetarian

A QiMeal recipe · Updated 3 October 2026

Ingredients · 2 servings

4 sliceSourdough, sliced
120 gCaramelized onion, prepared
100 gGruyere, grated
1 tspThyme, leaves only
28 gButter, softened
¼ tspSalt
¼ tspBlack pepper, ground

Equipment

stovetop, skillet, spatula, grater, knife, cutting board, measuring spoon, small bowl, butter knife, spoon, serving plate

Instructions

Gather Ingredients
Gather sourdough, caramelized onion, Gruyere, thyme, butter, salt, pepper, a skillet, spatula, grater, knife, and board. · 5 min
What to look for: All ingredients and tools are ready on the work surface.
Prepare Filling
Grate Gruyere, strip thyme leaves, and season the caramelized onion lightly with salt and black pepper. · 4 min
What to look for: Cheese is fluffy, thyme is leafy, and onion looks glossy.
Butter Bread
Spread softened butter on 1 side of each sourdough slice, keeping the unbuttered sides ready for filling. · 3 min
What to look for: Each outside bread face has an even butter layer.
Build Sandwiches
Place 2 slices butter side down, add Gruyere, caramelized onion, thyme, and more Gruyere, then cap with remaining bread. · 4 min
What to look for: Filling is centered and enclosed between buttered sourdough slices.
Heat Skillet
Heat a heavy skillet over medium low heat until evenly warm, then place both sandwiches in the pan. · 2 min
What to look for: Butter begins to sizzle softly when the bread touches the pan.
Grill First Side
Cook the sandwiches until the bottom bread is deep golden and the cheese near the edges begins to soften. · 5 min
What to look for: Bottom crust is evenly golden and cheese looks glossy at the edges.
Flip Sandwiches
Turn each sandwich with a spatula, press gently, and cook until the second side is golden and the Gruyere melts. · 5 min
What to look for: Both sides are crisp and the cheese is melted through the center.
Rest And Serve
Rest the sandwiches for 1 minute, slice each one in half, and serve hot while the Gruyere is fluid. · 1 min
What to look for: Sandwich halves hold together with molten cheese and glossy onion inside.

Nutrition (per serving)

kcal	590
Protein	25 g
Carbohydrates	53 g
of which sugars	6 g
Fat	31 g
of which saturated	17 g
Fibre	3 g
Sodium	925 mg

Nutri-ScoreD

Allergens

Contains: gluten, milk

Storage and reheating

Fridge: up to 2 days
Freezer: not recommended
Reheat until the bread is crisp and the cheese is hot, checking often so the sourdough does not darken too much.

Ingredient substitutions

Thyme

Black pepper: Use only if thyme is unavailable, since the herbal French onion character will be reduced.

Butter

Olive oil: Brush lightly on the bread for browning, though the flavor will be less buttery.

Salt

Black pepper: Use less pepper if skipping salt, since it adds aroma rather than salinity.

Black pepper

Thyme: Use extra thyme for aroma if pepper is omitted.