Rinse trimmed chicken livers under cold water and pat dry with paper towels. Remove any connective tissue or greenish bits. Season lightly with 1/2 teaspoon salt and 1/4 teaspoon black pepper.

Sauté Aromatics

In a large skillet, melt 2 tablespoons butter over medium heat. Add the finely chopped shallot and cook, stirring, until soft and translucent, about 4 minutes. Add minced garlic and thyme and cook 30 seconds more until fragrant.

Cook Livers

Increase heat to medium-high, add the livers to the skillet in a single layer and sear until the outside is browned but the centers remain slightly rosy, about 2 to 3 minutes per side. Avoid overcooking; internal texture should be tender.

Flambé / Deglaze

Remove the pan from heat. Carefully add the brandy or cognac, return to low heat and ignite with a long match if comfortable to flambé to burn off alcohol (optional). Alternatively, simply deglaze by stirring and scraping up browned bits for 30–60 seconds.

Blend Mousse

Transfer contents of the pan (livers, shallots, juices) to a food processor or blender. Add remaining 2 tablespoons butter (cold, cubed) and the heavy cream. Puree until completely smooth, about 1–2 minutes. Taste and adjust seasoning with remaining salt, pepper and lemon juice. For an extra-silky texture, pass the purée through a fine-mesh sieve into a bowl.

Chill

Pack the mousse into a serving terrine or individual ramekins. Smooth the surface, cover with plastic wrap (touching the surface to prevent skin) and chill in the refrigerator at least 2 hours to firm.

Port Aspic

Bloom the gelatin by sprinkling powdered gelatin over 2 tablespoons cold water in a small bowl. Let sit 5 minutes until softened.

In a small saucepan, combine 1 cup ruby port, 1/4 cup water and 1 tablespoon sugar. Warm gently over medium heat until sugar dissolves and the liquid is hot but not boiling.

Remove pan from heat, stir in bloomed gelatin until fully dissolved. Taste and adjust sweetness if needed. Let the liquid cool to lukewarm (about 10–15 minutes).

When the mousse has set and just before serving, pour a thin layer (about 2–3 tablespoons) of the cooled port aspic over the chilled mousse to create a glossy, flavorful seal. Return to refrigerator for 15–20 minutes to set the aspic layer.

Green Apple Compote

In a medium saucepan, melt 1 tablespoon butter over medium heat. Add diced green apples, 2 tablespoons sugar, 1 tablespoon lemon juice and 1 tablespoon apple liqueur (if using).

Cook, stirring occasionally, until apples are tender but still hold some shape, about 6–8 minutes. If mixture becomes too dry, add 1–2 tablespoons water. Season with 1/4 teaspoon salt and remove from heat. Let cool to room temperature; compote will thicken slightly as it cools.

To Serve / Finish

Prepare sourdough: brush both sides of each slice with olive oil and grill or toast over medium-high heat until golden and crisp, about 2 minutes per side. Rub lightly with a cut clove of garlic if desired (optional).

Assemble: Remove mousse from ramekins or slice terrine. Spoon a small quenelle or dollop of green apple compote alongside or on top of the mousse. Garnish with a few small spoonfuls of port aspic (or a few decorative shards if fully set) and sprinkle microgreens or chopped chives and a pinch of sea salt flakes.

Serve immediately with grilled sourdough slices. Leftover mousse keeps refrigerated up to 3 days; the aspic may weep slightly over time.