I think you are referring to a proposal by Moshe Dayan to Meir in December 1970 that Israel withdraw 20 miles from the Suez Canal in order to aid the Egyptians in reopening the canal and possibly averting their motivation to go to war, according to this article in the Times of Israel. Two months later, Sadat, in a speech to the Egyptian National Assembly adopted Meir's proposal, but his proposal did not include recognition of Israel or a willingness to negotiate and agree on border, two items that were fundamental Israeli demands, and things that Sadat ultimately agreed to with Begin. Moreover, the article asserts that Israel was advised by the Nixon administration not to agree to Sadat's proposal without further conciliatory gestures from Sadat.
In 2013, the Israeli government released documents that in early June 1973, Israel sent Sadat a secret message through West German Chancellor Willy Brandt, proposing that Israel would be willing secretly meet with Sadat to trade Sinai to Egypt for peace. In a later meeting she described the offer, saying: "He can tell Sadat that he, Brandt, is convinced that we truly want peace. That we don’t want all of Sinai, or half of Sinai, or the major part of Sinai. Brandt can make it clear to Sadat that we do not request that he begin negotiations in public, and that we are prepared to begin secret negotiations, etc." For the original Hebrew-language document, see Document 8.
Coming so closely after the 1972 Munich massacre of Israeli atheletes, Brandt was not so willing to involve West Germany in the negotiations at a high level. He sent a relatively low-level diplomat to meet with Egyptian officials. According to a 2013 Times of Israel article, Hafiz Ismail, a close adviser to Egyptian president Anwar Sadat, and relayed the Israeli proposal, advised Sadat to reject the offer on the basis that unless Israel was willing to retreat to the pre-1967 cease-fire lines, there was no point in talking directly with the Jewish state.
Meir's disappointment with Sadat's failure to accept her offer to meet was reflected in her first comment to him when they met on his first visit to Israel in 1977, where she said simply, "what took you so long?" Hinn, Benny, Blood in the Sand, p. 150.