Yes, the answer was there, after adding the double.infinity for the width and the height, the image was expanded. the final code I used was like this:

 Expanded(
          child: Image.asset(
            'assets/coffee-beans-bg.jpg',
            width: double.infinity,
            height: double.infinity,
            fit: BoxFit.fill, // Ensures the image fits the full width
          ),
        ),