In parshat Vayera, Bereishit 18:7, the text relates that
וְאֶל־הַבָּקָ֖ר רָ֣ץ אַבְרָהָ֑ם וַיִּקַּ֨ח בֶּן־בָּקָ֜ר רַ֤ךְ וָטוֹב֙ וַיִּתֵּ֣ן אֶל־הַנַּ֔עַר וַיְמַהֵ֖ר לַֽעֲשׂ֥וֹת אֹתֽוֹ׃
Avraham ran, chose an animal, gave it to the youth "and he rushed to do it." (the Haemek Davar says that it means that Avraham rushed the lad to do it)
Instead of any detail given about what was being done, or any verb specific to food preparation, the text simply says "la'asot oto" to do "it". The Radak indicates that the "do" was to prepare/cook the food, but the word seems unnecessarily vague.
As far as I understand, "la'asot" indicates doing an action, with the object (that which is done) usually a specified task. Here, the object is either the unlisted command [cf pasuk 19 "לַעֲשׂוֹת צְדָקָה וּמִשְׁפָּט"], or the animal (as other transitive verbs are followed by the object of that verb). The term "la'asot oto" only appears one other time in the Chamisha Chumshei Torah, in Vayikra 17:9 but there the action done is explicitly spelled out in the previous verse (אֲשֶׁר יַעֲלֶה עֹלָה אוֹ זָבַח) . Why would the text use such vague language?
The Chizkuni writes about the phrase "לשון תקון" but I'm not sure what he means by that.
Is there any other discussion/insight into why the text does not say exactly what was done?