Preheat a skillet or griddle over medium heat. Brush both sides of the sourdough slices lightly with the 2 tbs olive oil (or spread butter if using). Toast the slices 2–3 minutes per side until golden and crisp with nice grill marks. Transfer to a rack to keep crisp.

Whipped chèvre spread

Make whipped chèvre

Place the crumbled chèvre, Greek yogurt, and 1 tbs milk in a food processor or a mixing bowl. Add lemon zest, lemon juice, 1 tsp sea salt, and 1 tsp black pepper. Blend or beat until smooth and creamy, adding the remaining 1 tbs milk only if needed to reach a spreadable consistency. Taste and adjust salt, pepper or lemon as needed. Transfer to a bowl and refrigerate briefly if you prefer it chilled.

If you do not have a food processor, whip the chèvre vigorously with a whisk or electric mixer until smooth, scraping the bowl to ensure even texture.

Green tomatoes & topping

Prepare tomatoes

Slice the green tomatoes about 1/8-inch thick. Lay slices on paper towel and sprinkle lightly with a pinch of salt; let sit 5 minutes to draw out excess moisture, then pat dry to prevent soggy toast.

Assemble toppings

In a small bowl combine the chopped dried Niçoise olives, chopped parsley, chives, capers (if using), and red pepper flakes. Toss gently to mix.

Assembly & finishing

Build the tartines

Spread a generous 2 tbs of whipped chèvre over each toasted sourdough slice, leaving a small border. Arrange overlapping green tomato slices on top of the chèvre to cover the bread.

Scatter the olive-herb mixture evenly over the tomato layers, distributing capers and herbs so each tartine gets flavor in every bite.

Finish each tartine with a light drizzle (about 1/4 tsp) of the 1 tsp finishing olive oil, a tiny drizzle (about 1/8 tsp) of white balsamic or sherry vinegar if using, a pinch of flaky sea salt, and a crack of fresh black pepper.

Serve immediately while toast is crisp. Optionally garnish with additional basil chiffonade and an extra sprinkle of red pepper flakes for heat.