Mint Chocolate Sheet Cake Recipe

<ul class="ingredients-main-list"><li class="ingredients-single-item">280g all-purpose flour</li><li class="ingredients-single-item">400g granulated sugar</li><li class="ingredients-single-item">80g unsweetened cocoa powder</li><li class="ingredients-single-item">2 tsp baking soda</li><li class="ingredients-single-item">1 tsp baking powder</li><li class="ingredients-single-item">1 tsp salt</li><li class="ingredients-single-item">240ml buttermilk</li><li class="ingredients-single-item">120ml vegetable oil</li><li class="ingredients-single-item">2 large eggs, room temperature</li><li class="ingredients-single-item">2 tsp pure peppermint extract</li><li class="ingredients-single-item">240ml hot coffee (or hot water)</li><li class="ingredients-single-item">For the mint frosting:</li><li class="ingredients-single-item">225g unsalted butter, softened</li><li class="ingredients-single-item">500g powdered sugar</li><li class="ingredients-single-item">3 tbsp heavy cream</li><li class="ingredients-single-item">1½ tsp pure peppermint extract</li><li class="ingredients-single-item">Green food coloring (optional)</li><li class="ingredients-single-item">Pinch of salt</li><li class="ingredients-single-item">For the chocolate ganache:</li><li class="ingredients-single-item">170g dark chocolate, chopped</li><li class="ingredients-single-item">120ml heavy cream</li><li class="ingredients-single-item">50g crushed peppermint candies, for garnish</li></ul>

<ul class="equipment-main-list"><li class="equipment-single-item">33x23cm (13x9-inch) baking pan</li><li class="equipment-single-item">Stand mixer or electric hand mixer</li><li class="equipment-single-item">Offset spatula</li><li class="equipment-single-item">Parchment paper</li></ul>

<ol class="no-list-style"><li class="MethodStepper"><h4 class="step-title">Step 1</h4>Preheat your oven to 180°C (350°F). Line your 33x23cm baking pan with parchment paper, leaving some overhang on the sides for easy removal, and lightly grease any exposed pan sides.</li><li class="MethodStepper"><h4 class="step-title">Step 2</h4>In a large bowl, whisk together the flour, sugar, cocoa powder, baking soda, baking powder, and salt until thoroughly combined. The cocoa powder tends to form lumps, so be particularly thorough when whisking.</li><li class="MethodStepper"><h4 class="step-title">Step 3</h4>In a separate medium bowl, whisk together the buttermilk, vegetable oil, eggs, and peppermint extract until smooth. The buttermilk's acidity will react with the baking soda to create a tender crumb and help the cake rise.</li><li class="MethodStepper"><h4 class="step-title">Step 4</h4>Pour the wet ingredients into the dry ingredients and whisk until just combined. Don't overmix at this stage or your cake may become tough. The batter will be thick.</li><li class="MethodStepper"><h4 class="step-title">Step 5</h4>Add the hot coffee (or hot water) and whisk until the batter is smooth. The hot liquid helps bloom the cocoa powder, intensifying the chocolate flavor. The batter will now be quite thin – this is exactly what you want for a moist cake!</li><li class="MethodStepper"><h4 class="step-title">Step 6</h4>Pour the batter into your prepared pan and bake for 32-35 minutes, or until a toothpick inserted in the center comes out with just a few moist crumbs (not wet batter). Don't overbake – this is what keeps the cake moist and fudgy.</li><li class="MethodStepper"><h4 class="step-title">Step 7</h4>Allow the cake to cool completely in the pan on a wire rack before frosting. This will take about 1-2 hours. Patience is key here – frosting a warm cake will cause the frosting to melt.</li><li class="MethodStepper"><h4 class="step-title">Step 8</h4>For the mint frosting, beat the softened butter in a large bowl using an electric mixer until creamy and pale, about 2-3 minutes. The extended beating incorporates air for a fluffy frosting.</li><li class="MethodStepper"><h4 class="step-title">Step 9</h4>Gradually add the powdered sugar, one cup at a time, beating well after each addition. Add the heavy cream, peppermint extract, a few drops of green food coloring (if using), and salt. Beat on medium-high speed until light and fluffy, about 3-4 minutes.</li><li class="MethodStepper"><h4 class="step-title">Step 10</h4>Spread the mint frosting evenly over the cooled cake using an offset spatula. Create decorative swirls if desired. Place the frosted cake in the refrigerator for about 15 minutes to set the frosting before adding the ganache.</li><li class="MethodStepper"><h4 class="step-title">Step 11</h4>For the chocolate ganache, place the chopped chocolate in a heatproof bowl. Heat the heavy cream in a small saucepan until it just begins to simmer (don't let it boil). Pour the hot cream over the chocolate and let it sit for 2-3 minutes without stirring (this allows the chocolate to melt evenly).</li><li class="MethodStepper"><h4 class="step-title">Step 12</h4>Gently whisk the chocolate and cream mixture until smooth and glossy. Allow the ganache to cool slightly until it thickens but is still pourable, about 5-10 minutes. The temperature of the ganache is crucial – too hot and it will melt your frosting, too cool and it won't spread properly.</li><li class="MethodStepper"><h4 class="step-title">Step 13</h4>Pour the ganache over the chilled frosted cake, using an offset spatula to spread it evenly if needed. Work quickly as the ganache will begin to set when it hits the cold frosting.</li><li class="MethodStepper"><h4 class="step-title">Step 14</h4>Immediately sprinkle the crushed peppermint candies over the ganache before it sets. For the best presentation, focus the candies in the center or create a pattern across the top.</li><li class="MethodStepper"><h4 class="step-title">Step 15</h4>Refrigerate the cake for at least 30 minutes to allow the ganache to set completely before slicing. For serving, bring the cake to room temperature for about 20 minutes to allow the flavors to fully bloom – the mint and chocolate notes will be more pronounced at room temperature.</li></ol>