This sub is making me broke

I could not get cardamom flavor on Milky Cake, I went for Onyx's V60 recipe with 1:16 ratio with 97C water. What can I do to have more flavor with milky cake?

I could not get cardamom flavor on Milky Cake, I went for Onyx's V60 recipe with 1:16 ratio with 97C water. What can I do to have more flavor with milky cake?