You cannot stir-fry amaranth without blanching it. The amaranth needs to be blanched.

No, amaranth needs to be blanched. The oxalic acid content in amaranth is very high, and eating it without blanching is not good for your health. Moreover, the taste of amaranth will be more delicious after it is blanched. However, it should be noted that the time to blanch amaranth should be short and fast, otherwise the taste will be affected.