1. Preheat the oven to 350F (180C). 2. Arrange the sardines in the single layer in a baking dish, sprinkle with salt and pepper, and bake until just cooked, about eight minutes. 3. Remove from oven and let cool to room temperature. 4. Pulse the sardines in a food processor, or mash them with a fork, along with the shallots, chives, chile powder, butter, and olive oil, until relatively smooth, but still a bit chunky. 5. Add a squeeze of lemon juice and taste, adjusting the seasonings to your liking. 6. Scrape the mixture into a small bowl and chill for at least eight hours, or overnight. 7. Let come to room temperature before serving.