Marshmallows:

Line an 8 x 8-inch square tin with parchment in a criss-cross pattern, allowing a 1-inch overhang on all sides. Spray with nonstick spray.

Pour 120 milliliters (1/2 cup) water into a large mixing bowl or the bowl of a stand mixer. Sprinkle powdered gelatin evenly over the water. Set aside.

In a large, heavy-bottomed stock pot, combine granulated sugar, corn syrup, remaining water, and fine sea salt. Bring to a boil and boil, without stirring, until syrup reaches 240° F / 116° C on a digital thermometer.

Carefully pour hot syrup over gelatin mixture. Mix on high speed for 2-3 minutes, or until mixture turns white and begins to thicken.

Add watermelon flavoring and pink gel food coloring and continue mixing on high speed until very thick and voluminous, about 6-8 minutes more.

With an oiled flexible rubber spatula, fold in the miniature chocolate chips.

Scrape into prepared tin. Scatter with more miniature chocolate chips to mimic “watermelon seeds.”

Loosely cover with a well-oiled sheet of aluminum foil. Allow to set at room temperature until firm, at least 4 hours, or overnight.

Cutting and Coating:

Line your work surface or a half sheet rimmed baking tray with a silicone mat. Set aside.

In a small bowl, whisk together cornflour and confectioner’s sugar.

Place a sheet of parchment over a large cutting board. Dust with the cornflour and confectioner’s sugar mixture.

Turn marshmallow slab out onto dusted surface. Peel away parchment. Sift with more of the powder.

With a well-oiled chef’s knife or an oiled 2-inch triangle cutter, cut slab into triangles. I cut four 2-inch wide rows, then cut each row into six 2-inch wide triangles.

Toss in additional powder, coating all sides evenly. Arrange on prepared silicone mat.

With a pastry brush, brush away excess powder. Arrange triangles on a clean silicone mat or fresh sheet of parchment.

In a double boiler, bain-marie, or a microwave-safe bowl, melt green candy melts, stirring occasionally until completely melted. Add 1-2 teaspoons vegetable oil, or more as needed, until chocolate reaches a smooth, fluid, and easily dippable consistency.

Dip the flat portion of each triangle in the melted chocolate, completely covering the bottom and creating a 1/4 – 1/2-inch “rind” around all sides.

Allow marshmallows to sit, uncovered, at room temperature until chocolate sets.

Layer between sheets of wax paper or parchment. Store in an airtight container at room temperature for up to 3 weeks.