Preheat and prep: Heat your oven to 325°F (163°C). Grease a 2-quart baking dish or an 8-inch square pan. For easier serving, you can also line it with a parchment sling.

Melt the butter: In a small saucepan or microwave-safe bowl, melt the butter until smooth. Let it cool slightly so it doesn’t scramble the eggs later.

Whisk the sugars and eggs: In a large bowl, whisk granulated sugar, brown sugar, and eggs for about 1–2 minutes until slightly thick and glossy. This helps create that signature crust.

Add vanilla and butter: Whisk in vanilla, then slowly stream in the warm melted butter while whisking constantly. The mixture should look shiny and cohesive.

Sift in dry ingredients: Sift cocoa powder, flour, espresso powder (if using), and salt over the bowl. This prevents lumps and keeps the batter silky.

Fold gently: Use a spatula to fold until just combined. Avoid overmixing. If using chocolate chips, fold them in now.

Pour and smooth: Scrape the batter into your prepared dish and smooth the top. It will be thick—that’s good.

Bake: Bake for 35–45 minutes, depending on your pan and how gooey you like it. The edges should be set, the top should be crackly, and a toothpick inserted near the edge comes out mostly clean while the center remains soft.

Rest briefly: Let the pudding sit for 10–15 minutes. It will settle into that luscious, spoonable texture.

Serve warm: Spoon into bowls and top with ice cream or whipped cream. A sprinkle of flaky salt is amazing here.