In a recycled mansion on the west side of the Río Tigre, the family-run Casona la Ruchi (Lavalle 557, tel. 011/4749-2499, www.casonalaruchi.com.ar [1], US$55 d with shared bath) has five spacious rooms, attractive gardens, and a pool.
Standard Argentine eateries are a dime a dozen at locales like the Mercado de Frutos. For a more sophisticated menu on a shady riverside terrace with good service, try
María Luján (Paseo Victorica 611, tel. 011/4731-9613, www.ilnovomariadellujan.com [2]). Homemade pastas cost around US$7–10, more elaborate dishes around US$9–12.
Links:
[1] http://www.casonalaruchi.com.ar
[2] http://www.ilnovomariadellujan.com