Preheat the oven to 350°F (175°C). Grease an 8-inch square pan with oil. Skip the parchment, since the cake stays in this pan through soaking and serving.

Whisk the oil and sugar for 2 to 3 minutes until smooth and the sugar mostly dissolves.

Stir the yogurt and baking soda together in a small bowl and let it rest for 2 minutes until foamy.

Add the yogurt mixture and vanilla to the oil and sugar, and whisk well.

Sift in the flour, baking powder and salt. Fold gently until just combined. Overmixing gives a dense sponge that won't soak well.

Spread the batter evenly in the pan and bake for 25 to 30 minutes, until a toothpick comes out clean.

Cool completely in the pan, at least 1 hour.

Blend the evaporated milk, paan leaves, fennel seeds and gulkand together until smooth. Add green gel food color, if desired.

Strain through a fine mesh strainer, pressing on the solids. Discard the pulp.

Stir in the condensed milk and heavy cream (or full-fat milk). Taste it, it should be sweet, floral and gently fennel-forward.

Poke holes all over the cooled cake, about three-quarters of the way down and an inch apart.

Set aside about 1¼ cups (300 ml) of the paan milk to serve with the slices.

Pour the rest over the cake in stages, about ½ cup at a time, letting each addition absorb for 5 to 10 minutes.

Cover tightly and refrigerate for at least 6 hours, ideally overnight.

To a mixing bowl, add the cold cream, powdered sugar, pink gel food color(optional), and rose water. Whip on high speed until stiff peaks form, about 2 to 3 minutes. Stop as soon as the peaks hold.

Spread or pipe the cream over the chilled cake and garnish with candied fennel.

Cut into 9 squares and spoon a little of the reserved paan milk around each slice.