Smoked Salmon Sandwich

Name: Smoked Salmon Sandwich
Prep time: 10 min
Total time: 10 min
Cuisine: European
Ingredients: ⅓ cup cream cheese (75 g, Note 1); 1 heaped tablespoon Greek yogurt; a pinch of chili flakes (or cayenne pepper, to taste); small handful of arugula; 2 slices sourdough bread (Note 2); 2.5 oz smoked salmon ( 75 g, Note 3); 1 tablespoon capers; a squeeze of fresh lemon juice; 1 tablespoon chives (chopped ); fine sea salt and freshly ground black pepper