Preheat and prep: Heat your oven to 350°F (175°C). Line two baking sheets with parchment paper. This helps prevent spreading and keeps cleanup easy.

Whisk the wet ingredients: In a large bowl, whisk olive oil, granulated sugar, and brown sugar until glossy and well combined, about 30 seconds. Add the non-dairy milk and vanilla, and whisk again until the mixture looks smooth and slightly thick.

Mix the dry ingredients: In a separate bowl, whisk flour, cornstarch, baking soda, baking powder, and salt. This step prevents clumps and ensures even rise.

Combine: Add the dry ingredients to the wet mixture. Stir with a spatula until just combined. The dough should be soft but not greasy. Avoid overmixing to keep the cookies tender.

Fold in chocolate: Stir in the chocolate chips or chunks until evenly distributed. If the dough feels loose, let it rest for 5–10 minutes; it will firm up slightly as the flour hydrates.

Scoop: Use a 1.5-tablespoon cookie scoop or heaping tablespoon to portion the dough onto the lined sheets, spacing about 2 inches apart. For thicker cookies, chill the scooped dough for 15–20 minutes before baking.

Bake: Bake for 9–12 minutes, until the edges are set and lightly golden but the centers still look soft. Rotate the pans halfway through for even baking.

Finish: While the cookies are hot, gently tap the baking sheet on the counter to help them settle and get those pretty rippled edges. Sprinkle with flaky sea salt if you like.

Cool: Let cookies cool on the sheet for 5 minutes, then transfer to a rack to cool completely. They’ll firm up as they cool, keeping that chewy middle.