to have the upper hand, to hold all the aces
Agora sou rico, poderoso e influente, tenho a faca e o queijo na mão!
Now I'm rich, powerful and influential, I hold all the aces!
The image is concrete: someone holding both the knife and the cheese has everything needed to cut a slice right away — only the act itself remains. To estar com a faca e o queijo na mão ("to be with the knife and the cheese in hand") is therefore to hold every advantage and full control over a situation.
Source: escreva.ai.
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