cut the vegetables, turn on the heat, put them in the pan....
「お野菜切って」= cut the vegetables
「火を付けて」= turn on the heat
「お鍋に入れて」= put them/the vegetables in the pan
「混ぜて」= stir/the vegetables 又は stir them/give them a stir
「盛り付けて」= dish them up 又は put them on a plate/in a bowl
「はい出来上がり」= It's ready! 又は Dinner/lunch is ready!
「召し上がれ」= Let's eat 又は Come and eat it!
何かの作り方を言う・教える際、「命令」の文法を使います。つまり、主語を使わないで動詞だけを使います。例えば、 「cut ~」、「put ~」、「stir ~」など。
Prepare/cut the vegetables, turn on the gas, put the vegies into the pot, stir them up, put them on the plate, then...it's ready! Here you are/There you go!