Is the word assado the same in Brazilian and European Portuguese?

Yes

The word "assado" has the same meaning, spelling, and grammatical function in both Brazilian and Continental Portuguese. The differences are strictly related to pronunciation:

• Vowel reduction: In Continental Portuguese, unstressed vowels (like the "o" in assado) are often reduced or shortened, making the word sound more clipped. In Brazilian Portuguese, vowels are typically more open and clearly articulated.
• Sibilance: Depending on the region of Brazil, the "ss" may be pronounced as a sharp [s] (common in São Paulo) or a "sh" [ʃ] sound (common in Rio de Janeiro), whereas in Portugal, it is consistently a [s] sound.

Brazilian Portuguese Examples:

1. O frango assado está uma delícia. (The roasted chicken is delicious.)
2. Eu adoro comer carne assada no domingo. (I love eating roasted meat on Sundays.)
3. O cheiro do bolo assado está maravilhoso. (The smell of the baked cake is wonderful.)
4. A batata assada ficou muito crocante. (The roasted potato turned out very crispy.)
5. Vamos fazer um assado para o almoço? (Shall we make a roast for lunch?)

Portuguese (Continental) Examples:

1. O frango assado está uma maravilha. (The roasted chicken is wonderful.)
2. Gosto de comer carne assada ao domingo. (I like to eat roast meat on Sundays.)
3. O cheiro do bolo assado está ótimo. (The smell of the baked cake is great.)
4. As batatas assadas ficaram bem estaladiças. (The roasted potatoes turned out very crispy.)
5. Vou preparar um assado para o jantar. (I am going to prepare a roast for dinner.)